Macrolide antiinfective agents

ABSTRACT

Compounds of the formula                    
     wherein 
     R a  is H; substituted or unsubstituted alkyl (1-10C); substituted or unsubstituted alkenyl (2-10C); substituted or unsubstituted alkynyl (2-10C); substituted or unsubstituted aryl (4-14C); substituted or unsubstituted arylalkyl (5-20); or OR a  is replaced by H; 
     R b  is H or halogen; 
     R c  is H or a protecting group; 
     R d  is methyl, unsubstituted alkyl (3-10C); substituted alkyl (1-10C); substituted or unsubstituted alkynyl (2-10C); substituted or unsubstituted aryl (4-14C); substituted or unsubstituted arylalkyl (5-20C); substituted or unsubstituted arylalkenyl (5-20C); substituted or unsubstituted arylalkynyl (5-20C); substituted or unsubstituted amidoarylalkyl (5-20C); substituted or unsubstituted amidoarylalkenyl (5-20C); or substituted or unsubstituted amidoarylalkynyl (5-20C); 
     R e  is H or a protecting group; 
     L is methylene or carbonyl; 
     T is —O—, —N(R)—, —N(OR)—, —N(NHCOR)—, —N(N═CHR)—, or —N(NHR)— wherein R is H or R a  as defined above, with the proviso that when L is methylene, T is —O—; 
     one of Z and Y is H and the other is OH, protected OH, or amino, mono- or dialkylamino, protected amino, or an amino heterocycle or 
     Z and Y together are ═O, ═NOH or a derivatized oxime; 
     including any pharmaceutically acceptable salts thereof and any stereoisomeric forms and mixtures of stereoisomeric forms thereof, are antimicrobial agents.

This application claims priority under 35 U.S.C. §119 from U.S.provisional patent application Serial Nos. 60/129,729 filed Apr. 16,1999, 60/172,154 filed Dec. 17, 1999, 60/140,175 filed Jun. 18, 1999,60/172,159 filed Dec. 17, 1999, 60/173,805 filed Dec. 30, 1999, and60/173,804 filed Dec. 30, 1999, and U.S. utility patent application Ser.No. 09/551,162 filed on Apr. 14, 2000 entitled “MacrolideAntiinfectives”. The contents of these applications are relied on andincorporated herein in their entirety by reference.

TECHNICAL FIELD

The invention is directed to antibacterial compounds that expand therepertoire of erythromycin-like antibiotics. More particularly, theinvention concerns macrolide antibiotics containing an erythronolidenucleus modified at least at the substituent at C-13.

BACKGROUND ART

The increasing number of microbial strains that have acquired resistanceto the currently available known antibiotic compounds is recognized as adangerous threat to public health. As the use of such compounds hasproliferated, so too has the need for expanding the options available totreat a wide variety of microbial-based conditions. The need for alarger choice of antimicrobial compounds extends beyond treatment ofhuman infection and to a need to preserve food and other perishablecommodities. New antibiotics can also be essential for resistant plantsand animals as well as to provide resistance to materials that otherwiseare subject to microbially caused corrosion.

Thus, there is a clear need for an expanded armament of compounds whichcan provide a multifaceted defense against unwanted microbial activity.

WO 98/09978 published Mar. 12, 1998 and incorporated herein by referencediscloses modified forms of erythromycin which lack a cladinose residueat the 3-position and which are derivatized in various ways in positions9-12 of the macrolide ring. Similarly, U.S. Pat. No. 5,750,510, issuedMay 12, 1998 and incorporated herein by reference, discloses modifiederythromycin derivatives.

The naturally occurring erythromycins have the structure

wherein R′ can be H or OH and R″ can be H or CH₃.

All of the compounds disclosed in the above-referenced patent documentscontain an ethyl group at position 13 of the macrolide ring. The presentinventors have found that alterations in the substituent at position 13results in a large number of compounds with excellent antibacterialactivity.

DISCLOSURE OF THE INVENTION

The invention is directed to erythronolide derivatives that containmodifications from the native structure. All of the compounds of theinvention are modified at least at position 13 and have a ring at the11,12 position.

Thus, in one aspect, the invention is directed to compounds of theformula

wherein

R_(a) is H; substituted or unsubstituted alkyl (1-10C); substituted orunsubstituted alkenyl (2-10C); substituted or unsubstituted alkynyl(2-10C); substituted or unsubstituted aryl (4-14C); substituted orunsubstituted arylalkyl (5-20C); or OR_(a) may be replaced by H;

R_(b) is H or halogen;

R_(c) is H or a protecting group;

R_(d) is methyl, unsubstituted alkyl (3-10C); substituted alkyl (1-10C);substituted or unsubstituted alkenyl (2-10C); substituted orunsubstituted alkynyl; substituted or unsubstituted aryl (4-14C);substituted or unsubstituted arylalkyl (5-20C); substituted orunsubstituted arylalkenyl (5-20C); substituted or unsubstitutedarylalkynyl (5-20C); substituted or unsubstituted amidoarylalkyl(5-20C); substituted or unsubstituted amidoarylalkenyl (5-20C); orsubstituted or unsubstituted amidoarylalkynyl (5-20C);

R_(e) is H or a protecting group;

L is methylene or carbonyl;

T is —O—, —N(R)—, —N(OR)—, —N(NHCOR)—, —N(N═CHR)—, or —N(NBR)— wherein Ris H or R_(a) as defined above, with the proviso that when L ismethylene, T is —O—;

one of Z and Y is H and the other is OH, protected OH, or amino, mono-or dialkylamino, protected amino, or an amino heterocycle or

Z and Y together are ═O, ═NOH or a derivatized oxime;

including any pharmaceutically acceptable salts thereof and anystereoisomeric forms and mixtures of stereoisomeric forms thereof.

In another aspect, the invention is directed to pharmaceutical orpreservative compositions containing the compounds of formulas (1)-(3)and to methods to treat infectious diseases by administering thesecompounds or to preserve materials by providing them.

A BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic of the synthesis of intermediates for thecompounds of the invention.

FIG. 2 shows a schematic of the synthesis of the compounds of theinvention from these intermediates.

FIG. 3 shows a schematic of an alternate synthesis of the compounds ofthe invention from the intermediate compound (7).

FIGS. 4a and 4 b show a schematic of the synthesis of the compounds ofthe invention.

FIG. 5 shows a schematic of the synthesis of the inventive compoundswherein T is —O—.

FIG. 6 shows the post-PKS biosynthesis of erythromycins. This pathway isemployed in the present invention, as shown in FIG. 1.

FIG. 7 shows the synthesis of intermediate compounds of formula (4)wherein R_(a) is methyl.

FIG. 8 shows the synthesis of intermediate compounds of formula (6) andtheir corresponding 10,11-anhydro forms.

FIG. 9 shows the synthesis of intermediate compounds of formula (6)(anhydro form) wherein OR_(a) is replaced by H.

FIG. 10 illustrates the conversion of 15-azidoerythromycin A into15-amidoerythromycins.

FIG. 11 illustrates the conversion of 15-amidoerythromycins into thecorresponding 15-amido-6-O-alkyl-ketolide 11,12-cyclic carbamates.

FIG. 12 shows structures of particularly preferred examples of15-amido-6-O-alkyl-ketolide 11,12-cyclic carbamates. In each case, X maybe either H or F.

FIG. 13 illustrates the conversion of 15-ethenylerythromycin A into the15-ethenyl-6-O-alkyl-ketolide 11,12-cyclic carbamates, as well asoptional fluorination at C2.

FIG. 14 illustrates the attachment of aromatic groups onto the ethenylmoiety of 15-ethenylketolides to form 15-(2-arylethenyl)ketolides, andoptional hydrogenation to form the 15-(2-arylethyl)ketolides.

FIG. 15 shows structures of particularly preferred examples of15-(2-arylethenyl)-6-O-methyl-ketolide 11,12-cyclic carbamates and15-(2-arylethyl)-6-O-methyl-ketolide 11,12-cyclic carbamates. In eachcase, X may be either H or F.

FIG. 16 shows the synthesis of 15-ethenyl ketolides via olefinmetathesis.

MODES OF CARRYING OUT THE INVENTION

The compounds of the invention are conveniently synthesized by combiningsynthetic chemical techniques with microbiological processes involvinggenetically engineered microorganisms. Briefly, in a preferred mode ofcarrying out the invention, a microbial host, preferably a host whichdoes not itself produce a macrolide antibiotic, is provided with arecombinant expression system for the production of modified6-deoxyerythronolide B (6-dEB), which expression system in someinstances will have been altered by a disruption in the catalytic domainof the ketosynthase moiety in the first module. For substituents inwhich R_(d) is methyl, host cells are used which do not have a disrupteddomain of the ketosynthase moiety. This alteration in the 6-dEBpolyketide synthase (PKS) results in the inability of this PKS toutilize its native starter unit, and thus permits inclusion of asynthetic diketide thioester for its initial condensation product in thesequence of reactions leading to modified 6-dEB without competition fromthe diketide that would otherwise, natively, have been produced. Thus,the recombinant host can be provided a synthetic diketide thioester forincorporation into the resulting polyketide. The incorporation of thisdiketide into the resulting polyketide results in a polyketide with asubstituent at position 13 that may be selected as desired. Preferredmethods for preparing the synthetic polyketide thioesters are set forthin copending application U.S. Ser. No. 60/117,384 filed Jan. 27, 1999and 09/492,733 filed on Jan. 27, 2000, which are incorporated herein byreference.

Recombinant forms of the 6-dEB PKS containing inactivated ketosynthase(KS) domains in the first module (KS1) and appropriate organismsmodified to contain an expression system for this PKS are described inPCT applications WO 97/02358, published Jan. 28, 1997 and WO 99/03986,published Jan. 28, 1999, incorporated herein by reference.

The polyketide resulting from expression of the modified PKS is thenisolated and purified, if desired, from the recombinantly modifiedorganism and fed to Saccharopolyspora erythraea, which contains thefunctionality for postpolyketide modifications, including glycosylation.Other modifications include hydroxylation at positions 6 and 12. Theresulting modified erythromycin is then isolated and chemically modifiedto obtain the compounds of the invention. Synthetic methods forproviding these modifications are described in WO 98/09978 and U.S. Pat.No. 5,750,510, referenced hereinabove.

The general method for synthesizing intermediates to compounds of theinvention is shown in FIG. 1.

The method for synthesizing compounds from intermediates of theinvention is shown in FIG. 2.

The resulting antiinfective compound is active in vitro and in vivo foractivity against a panel of representative microorganisms. The compoundsof the invention thus exhibit a sufficient diversity in specificity tocover the spectrum of antibiotic activities desired.

For use in treating infectious disease, the compounds of the inventionare formulated into suitable compositions which will include typicalexcipients, pharmaceutically acceptable counterions if the compound is asalt, further additives as desired, such as antioxidants, buffers, andthe like, and administered to animals or humans. The types offormulations that are appropriate for these compounds are similar tothose for the macrolide antibiotics in general. Formulations may befound, for example, in Remington's Pharmaceutical Sciences, MackPublishing Co., latest edition. The compounds can be administered by anydesired route, including injection, oral administration, transdermaladministration, transmucosal administration, or any combination. Thecompounds of the invention can also be administered with additionalactive ingredients if desired.

The compounds of the invention are of formulas (1)-(3) as set forthabove, as well as any stereoisomeric forms of these compounds as shown.The particular stereoisomers depicted are those resulting from thepreferred method of synthesis set forth above and exemplified herein;however, by modifying the expression system for the PKS, or by alteringthe chirality of the diketide, or by synthetic chemical conversion,other stereoisomers may also be prepared. Additional chiral centers maybe present in the substituents, such as R_(a) and R_(d). Thestereoisomers may be administered as mixtures, or individualstereoisomers may be separated and utilized as is known in the art.

The properties of the compounds of formulas (1)-(3) are defined by thesubstituents R_(a)-R_(e), L, T, Y and Z. Preferred embodiments of thesesubstituents are set forth hereinbelow. They contain moieties which aredefined as follows:

“Halogen” includes fluoro, chloro, bromo and iodo, and most preferablyfluoro.

“Alkyl” refers to a saturated straight-chain, branched chain or cyclichydrocarbyl moiety containing a specified number of carbons and that maycontain one or more suitable heteroatoms; similarly, alkenyl and alkynylrefer to straight or branched chain or cyclic hydrocarbon substituentscontaining one or more double bonds or one or more triple bonds,respectively and that may contain one or more suitable heteroatoms.

“Aryl” refers to an aromatic substituent that may contain one or moresuitable heteroatoms such as phenyl, naphthyl, quinolyl, or phenanthryl.

“Arylalkyl,” “arylalkenyl,” or “arylalkynyl” refer to substituentswherein an aryl group is linked to the substituted moiety through analkyl, alkenyl or alkynyl linkage, respectively. Again, the number ofcarbons in the arylalkyl, arylalkenyl or arylalkynyl groups will bespecified.

“Amidoarylalkyl,” “amidoarylalkenyl,” or “amidoarylalkynyl” refer tosubstituents wherein an aryl group is linked to the substituted moietythrough an amido and an alkyl, alkenyl or alkynyl linkage, respectively.Again, the number of carbons in the amidoarylalkyl, amidoarylalkenyl oramidoarylalkynyl groups will be specified.

Thus, included among the defined substituents herein are “heteroalkyl,”“heteroalkenyl,” “heteroalkynyl,” “heteroaryl,” “heteroarylalkyl,” andthe like. Suitable heteroatoms include N, O, and S.

All of the foregoing substituents may be unsubstituted or may be furthersubstituted. Typical substituents include R, —OR, —SR, —NR₂, —COR,—COOR, —CONR₂, —OOCR, —NRCOR, —OCONR₂, —CN, —CF₃, —NO₂, —SOR, —SO₂R,halogen wherein each R is independently H or is alkyl, alkenyl, alkynyl,aryl, arylalkyl, or the hetero forms of these as defined above. Inaddition, alkyl, alkenyl and alkynyl may be substituted by aryl orheteroaryl, which may, themselves, be further substituted.

“A derivatized oxime” is of the formula ═N—O—R, wherein R is other thanH and is otherwise defined as above.

A “protecting group” for a hydroxy includes acyl groups, silyl groups,and the like. Suitable protecting groups are described by Greene, T. W.,et al., in Protecting Groups in Organic Sythesis, 2^(nd) Ed., John Wiley& Sons, Inc. (1991), incorporated herein by reference.

The invention includes more preferred embodiments of the compounddefined above. R_(d) is preferably butyl, pentyl, methoxyethoxymethyl,isobutyl, methylcyclohexyl, phenyl, benzyl, ethylphenyl,3-(benzyloxy)propyl, 2-(pyrimidin-2-ylthio)ethyl, propyl, fluoroethyl,chloroethyl, vinyl, 3-butenyl, or azidoethyl and more preferably propyl,fluoroethyl, chloroethyl, vinyl, 3-butenyl, or azidoethyl. U.S. Ser. No.60/117,384 filed Jan. 27, 1999 and U.S. Ser. No. 09/492,733 filed Jan.27, 2000 both of which are incorporated herein by reference describevarious oligoketide thioesters, preferably diketide thioesters, that canbe incorporated at the C-13 position. Such diketide thioesters asdescribed therein are incorporated into the compounds of the inventionand thus determine preferred R_(d) groups at the C-13 position.

In another preferred embodiment, R_(a) is H or lower C1-C3 alkyl, andmore preferably methyl. R_(a) is also preferably arylalkenyl orarylalkynyl such as 3-arylprop-2-enyl or 3-arylprop-2-ynyl. Preferablythe aryl group in the preferred arylalkenyl or arylalkynyl embodimentsare 3-quinolyl, 4-quinolyl, 5-quinolyl, phenyl, 4-fluorophenyl,4-chlorophenyl, 4-methoxyphenyl, 6-quinolyl, 6-quinoxalyl,6-amino-3-quinolyl, or 4-isoquinolyl.

When T—L—O forms a carbamate ring, a combination of substituents on thecarbamate nitrogen (R), the 6-O position (R_(a)), and the 13 position(R_(d)) are especially preferred. In a first preferred combination,R_(a) is preferably arylalkyl, arylalkenyl or arylalkynyl; R ispreferably H or substituted or unsubstituted lower alkyl; and R_(d) ispreferably substituted or unsubstituted alkyl. In these compounds R_(a)is more preferably arylpropyl, arylprop-2-enyl, or arylprop-2-ynyl; R ismore preferably hydrogen or methyl; and R_(d) is more preferably propyl,fluoroethyl, or chloroethyl.

In a second preferred combination, R_(a) is H or substituted orunsubstituted lower alkyl; R is preferably arylalkyl, arylalkenyl orarylalkynyl; and R_(d) is substituted or unsubstituted alkyl. In thesecompounds, R_(a) is more preferably methyl; R is more preferablyarylpropyl, arylprop-2-enyl, or arylprop-2-ynyl; and R_(d) is morepreferably propyl, fluoroethyl, or chloroethyl.

In a third preferred combination, when R_(a) is an unsaturatedsubstituent available for further derivatization such as alkenyl oralkynyl or other group such as azidoalkyl, then preferably R_(a) is H orsubstituted or unsubstituted lower alkyl, and R is H or substituted orunsubstituted lower alkyl. R_(a) is more preferably H or methyl and R ismore preferably H. Illustrative unsaturated substituents, R_(d) are morepreferably vinyl, propargyl, or butenyl, and other derivatizablesubstituents include azidoethyl. These compounds can be readilyderivatized by the methods of the invention to form from the unsaturatedsubstituents the arylalkyl, arylalkenyl, or arylalkynyl substituents andfrom the azido substiuent the amidoarylalkyl, amidoarylakenyl, oramidoarylakynyl substituent.

Preferred 15-amido ketolides, 15-ethenyl ketolides and other preferredarylsubstituted ketolides are shown in FIGS. 12 and 15.

Further, in one embodiment of compound (1) T is not N(R). In anotherembodiment of compound (1) T—L—O does not form a carbamate ring.

Synthesis of the Invention Compounds

As described above, the antibiotic starting materials for any furtherchemical synthesis are prepared, preferably, by feeding a suitablediketide to a microorganism modified to contain an expression system forthe 6-dEB PKS containing a KS1 knockout, or by a host cell that providesa methyl at the 13-position, followed by providing the resultingpolyketide to a recombinant strain of Saccharopolyspora erythraea thathas been altered to eliminate production of 6-dEB. A strain can beprepared that is able to hydroxylate both the 6- and 12-positions or the12-position only. In the latter case, —OR_(a) is replaced by —H. Therecombinant S. erythraes strain, K40-67, is obtained by transforming anS. erythraes strain that produces high levels of erythromycin A with aplasmid comprising a mutated eryA1 sequence encoding an inactivated KS1domain. By homologous recombination, the resulting transformants now areunable to produce 6-dEB as a competitor to the substrate polyketide and,instead, hydroxylate the 6-position and 12-position and glycosylate the3-position and 5-position of the modified polyketide that has been madein Streptomyces or other polyketide-producing transformant. If amacrolide having only the 12-position, and not the 6-positionhydroxylated is desired (OR_(a) is replaced by H), an S. erythraesstrain is constructed by disrupting the eryF hydroxylase gene in strainK40-67. Alternatively, the eryK gene can be disabled, whereinembodiments of compounds (1)-(3) may readily be produced.

Formation of the compounds of formulas (1)-(3) requires the productionof the erythronolide having a hydroxyl at the 12-position. The startingmaterial may include any of the compounds (4)-(6):

The glycosylation reactions for the production of the erythromycinsresult in the diglycosylated forms analogous to the compounds set forthin formula (4) herein. If the compounds of formula (4) are to beprepared from the initial product, the hydroxyl group of the cladinosering (attached to position 3) may then need to be protected forsubsequent modification of the macrolide substituents.

The modified erythromycins of the invention, in addition to modificationat C-13, contain an —OH group at position 6 unless OR_(a) is replaced byH as described above. To construct, ultimately, the compounds offormulas (1), (2) and (3) where position 6 is OR_(a), the compound offormula (I) (see FIG. 1) is provided with protecting groups which formone embodiment of R_(c) and R_(e). Such protection is effected usingsuitable protecting reagents such as acetic anhydride, benzoicanhydride, benzochloro formate, hexamethyldisilazane, or a trialkylsilylchloride in an aprotic solvent. Aprotic solvents include, for example,dichloromethane, chloroform, tetrahydrofuran, N-methyl pyrrolidone,dimethyl sulfoxide (DMSO), dimethyl formamide (DMF) and the like.Mixtures may also be used. Protection of both sugar hydroxyls in formula(I) may be done simultaneously or sequentially.

In addition to protecting the 2′ and 4″ hydroxyl groups of the twoglycose residues, the keto group at position 9 of the macrolide ringmust also be protected. Typically, this is effected by converting theketo group to a derivatized oxime. Particularly preferred embodimentsfor R in the formula ═NOR include unsubstituted or substituted alkyl(1-12C), substituted or unsubstituted aryl (6-10C), alkyl (1-12C),substituted or unsubstituted heteroaryl (6-10C), alkyl (1-12C), andheteroalkyl (such as substituents of the formula CR′₂OR wherein each R′,in addition to being independently embodied as R as set forth above,may, together with the other, form a cycloalkyl ring (3-12C)). Apreferred derivatized oxime is of the formula ═NOR wherein R isisopropoxycyclohexyl.

With the 9-keto group and the 2′ and 4″ hydroxyls protected, it is thenpossible to alkylate the 6-hydroxy group in the compound of formula (I)by reaction with an alkylating agent in the presence of base. Alkylatingagents include alkyl halides and sulfonates. For example, the alkylatingagents may include methyl tosylate, 2-fluoroethyl bromide, cinnamylbromide, crotonyl bromide, allyl bromide, propargyl bromide, and thelike. The alkylation is conducted in the presence of base, such aspotassium hydroxide, sodium hydride, potassium isopropoxide, potassiumt-butoxide, and an aprotic solvent.

The choice of alkylating agent will depend on the nature of thesubstituents R_(a) to be included. As set forth above, R_(a) can besubstituted or unsubstituted alkyl (1-10C), substituted or unsubstitutedalkenyl (2-10C), or substituted or unsubstituted alkynyl (2-10C).Particularly preferred are unsubstituted alkyl, alkenyl, or alkynyl, orsubstituted forms of these wherein the substituents include one or morehalogen, hydroxy, alkoxy (1-6C), oxo, SO₂R (1-6C), N₃, CN, and NR₂wherein R is H, substituted or unsubstituted alkyl (includingcycloalkyl) (1-12C), substituted or unsubstituted alkenyl (includingcycloalkenyl) (2-12C), alkynyl (including cycloalkynyl) (2-12C),substituted or unsubstituted aryl (6-10C), including the hetero forms ofthe above.

Especially preferred are methyl, allyl and ethyl.

Once the alkylation of the 6-hydroxyl is completed, the sugar residuesand the macrolide ring may be deprotected. Deprotection of the glycosidemoieties is conducted as described by Green, T. W., et al., inProtective Groups in Organic Synthesis, infra. Similar conditions resultin converting the derivatized oxime to ═NOH. If formation of theunderivatized oxime is not concurrent with deprotection, the conversionto the oxime is conducted separately.

The oxime can then be removed and converted to a keto group by standardmethods known in the art. Deoximating agents include inorganic sulfuroxide compounds such as sodium hydrogen sulfite, sodium pyrosulfate,sodium thiosulfate, and the like. In this case, protic solvents areused, such as water, methanol, ethanol, isopropanol, trimethyl silanoland mixtures of these. In general, the deoximation reaction is conductedin the presence of an organic acid.

At this point in the process, or later, after the compound of formula(4) has been converted to the compounds of formulas (5) or (6) or to anyof compounds (1)-(3), as further described below, the group introducedat the 6-hydroxyl can further be manipulated. Conveniently, the initialsubstitution may provide a 6—O-allyl, i.e., O—CH₂CH═CH₂, which canfurther be derivatized by reduction to give the 6-O propyl compound, orbe treated with osmium tetroxide to provide the 2,3-dihydroxypropylcompound, which can further be esterified at each oxygen atom. TheO-allyl derivative can also be oxidized with m-chloroperoxybenzoic acidin an aprotic solvent to provide the epoxy compound which can be openedwith amines or N-containing heteroaryl compounds to provide compoundswith N-containing side-chains, or can be oxidized under Wackerconditions to provide the substituent O—CH₂—C(O)—CH₃, or can be ozonizedto provide the aldehyde. The aldehyde can then be converted to the oximeor reacted with a suitable amine and reduced in the presence of aborohydride reducing agent to provide an amine. The oxime can also beconverted to a nitrile by reaction with a dehydration agent in anaprotic solvent. The O-allyl derivative can also be reacted with an arylhalide under Heck conditions (Pd(II) or Pd(O), phosphine and amine orinorganic base) to provide a 3-aryl prop-2-enyl derivative. Thisderivative can then be reduced with hydrogen and palladium on carbon toprovide a 3-arylpropyl derivative. If the initial substituent R_(a) is a2-propyne, similar reactions can be employed to provide alterations inthe side-chain, including arylation.

In order to convert the compound of formula (4) into the compound offormula (6), by first removing the cladinose moiety, the compound offormula (4) is treated with mild aqueous acid or with a deglycosylatingenzyme. Suitable acids include hydrochloric, sulfuric, chloroacetic,trifluoroacetic and the like, in the presence of alcohol. Reaction timesare typically 0.5-24 hours at a temperature of −10-35° C. During thisreaction, the 2′ group of the remaining sugar is protected as set forthabove and deprotected subsequent to the decladinizing reaction. Theresulting hydroxyl group at the 3-position of the macrolide ring is thenoxidized to the ketone using a modified Swern oxidation procedure. Inthis procedure, an oxidizing agent such as N-chlorosuccinimide-dimethylsulfide or a carbodiamide-dimethylsulfoxide is used. Typically, acompound of formula (4) is added to pre-formed N-chlorosuccinimide anddimethyl sulfide complex in a chlorinated solvent such as methylenechloride at −10-25° C. After being stirred for 0.5-4 hours, a tertiaryamine such as triethylamine is added to produce the corresponding ketoneand the 2′ protecting group is then removed.

In order to halogenate the macrolide at position 2 (converting R_(b)=Hto halogen), the compound of formula (6), where R_(b)=H, is treated witha base and an electrophilic halogenating reagent such as pyridiniumperbromide or N-fluorobenzenesulfonimide. Position 2 can be halogenatedat any time after the 3 keto compound is prepared and preferably afterthe 11,12 ring is formed.

The appropriate substituent such as vinyl, ethenyl, butenyl or azido atthe C-13 position can be further manipulated. For example, anamidoacetate salt of the compound of the invention can be derivatizedusing an arylacetyl chloride to yield an arylamino alkyl group on theC-13 position as illustrated in FIG. 10. Preferably the C13 derivativesof an azido group take place before the ketolide is formed. Derivationsof an alkenyl group such as ethenyl can take place either before orafter the ketolide is formed and preferably after the 11,12 ring isformed, as shown in FIGS. 14 and 16.

In order to obtain the compounds of formula (5), the compound resultingfrom the deglycosylation reaction of formula (4) is treated with adehydrating agent such as carbonyl diimidazole and base.

Intermediates (7)-(9) can then be prepared from intermediates (4)-(6).

It will be noted that the presence of the 12-hydroxyl group is required.The hydroxyl groups of the sugar moieties are protected as describedabove and the resulting protected compounds are then reacted with sodiumhexamethyldisilazide and carbonyldiimidazole which results indehydration to obtain a π-bond at position 10-11 and derivatization ofthe 12-hydroxyl to provide functionality in the macrolide ring as shownin compounds (7)-(9). FIG. 2 illustrates the reaction sequence fromcompound (4) to compound (9) in the first step.

Reaction of compounds (7)-(9) with aqueous ammonia provides a compoundof formulas (1)-(3) wherein L is carbonyl and T is NH as shown in FIG. 2for compounds (9) and (3) in the second step.

Reaction of compounds (7)-(9) with compounds of the formulas H₂NR,H₂NOR, H₂NNHCOR, H₂NN═CHR or H₂NNHR, where R is H or R_(a), provides thecorresponding compounds of formulas (1)-(3) wherein T is nitrogenderivatized as described with the R_(f) substituents including —R, —OR,—NHCOR, —N═CHR or —NHR. In FIG. 2, R_(f) is H because ammonia is used.These are compounds of the formulas (10)-(12):

where R_(f) represents the substituents on the nitrogen as describedabove. FIG. 3 analogously depicts the reaction of compound (7) withH₂NR_(f) to form compound (10). The preparation follows the proceduredescribed by Baker et al. J Org Chem (1988) 53:2340, which isincorporated herein by reference. In particular, treatment of compound(7) with an amino compound of the formula H₂N—R_(f) results in formationof the cyclic carbamate in which R_(f) is as described above. Theprotected 2′-hydroxy group can be deprotected as described above.

Alternate or additional procedures may be used to prepare compounds(10)-(12) where R_(f) is not H.

For example, the compounds of formulas (10)-(12) wherein R_(f) is H canbe reacted with an alkylating agent which is of the formula R-halogen toreplace the hydrogen on the ring nitrogen with an alkyl group.

Further, compounds (10)-(12) that do not contain an acyl group as asubstituent on the nitrogen of T can be formed by treatment of suchcompounds (10)-(12) with an acylating agent selected from the groupconsisting of R(CO)-halogen or (RCO)₂O to give compounds (7)-(9) whereinT is —N— and R_(f) is —NH—COR.

Treatment of compounds (10)-(12) where R_(f) is —NH₂ with an aldehydeR—CHO, wherein R is as defined previously gives compounds (10)-(12)wherein R_(f) is —N═CHR.

Treatment of compounds (10)-(12), where R_(f) is —NH₂ with an alkylatingagent having the formula R-halogen, wherein R is as defined previously,gives the compounds (10)-(12) where R_(f) is R.

Of course, if the substrate for the ring formation is a compound offormula (4), a compound of the formula (3) results; modifications canthen be conducted to convert the compound of formula (3) to compounds offormulas (1) and (2), as described above. Under these circumstances, theketo group would be protected by a derivatized oxime. Such modificationsinclude removal of the cladinose moiety by acid hydrolysis; oxidizingthe 3-hydroxyl group; and deprotecting the protected hydroxyl and ketogroups.

According to the alternate procedure shown in Ilustrated Scheme 4a FIG.4a), the intermediate compound (I₁), which is the 9-oxime compound oferythromycin A, is subjected to acid hydrolysis with dilute mineral ororganic acid as described previously to remove the cladinose moiety andgive intermediate compound (I₂). The oxime compound (I₂) is thenconverted to the protected oxime compound (I₃) wherein V is ═N—O—R¹where R¹ is a protecting group, by reaction with the appropriatelysubstituted oxime protecting reagent. The 3 and 2′-hydroxy groups of(I₃) are then protected, preferably with a trimethylsilyl protectinggroup, to give compound (I₄). Compound (I₄) is then alkylated asdescribed previously to give compound (I₅), and compound (I₅) is firstdeoximated as described above then the deoximated product is convertedto the compound (I₆) by the procedures described for preparation ofcompound (3) from compound (4) in Illustrated Scheme 2. FIG. 4b showscompound (₆) is then deprotected and oxidized to the 3-ketolidederivative, compound (10) of the invention, wherein L is CO and T is—NR_(f) by procedures described previously. Intermediate compound I₆ canalso be deprotected and dehydrated to form compound (11) of theinvention, also shown in FIG. 4b.

As mentioned earlier, the 6-position substituent can be manipulatedafter the compounds (1)-(3) are formed. For example, compound (10) canbe prepared wherein R_(a) is —CH₂—CH—N—OR_(h) and R_(h) is H orC₁-C₃-alkyl, aryl substituted C₁-C₃-alkyl, or heteroaryl substitutedC₁-C₃-alkyl. In this method, compound (10), wherein R_(a) is—CH₂—CH═CH₂, is treated with ozone to form compound (10) wherein R_(a)is —CH₂—CH═O.

The compound (10) wherein R_(a) is —CH₂—CH═O is further treated with ahydroxylamine compound having the formula NH₂—O—R_(h), wherein R_(h) isas previously defined; and optionally deprotecting, and isolating thedesired compound. In a preferred embodiment of the process immediatelyabove, R_(f) is H.

In another embodiment of the invention is a process for preparing acompound (10) wherein R_(a) is —CH₂—CH₂—NH—R_(i) where R_(i), with theatom to which it is attached, form a 3-10 membered substituted orunsubstituted heterocycloalkyl ring.

The method comprises reductively aminating compound (10) wherein R_(a)is —CH₂—CH═O with an amine compound having the formula —NH₂—R_(i),wherein R_(i) is as previously defined; and optionally deprotecting, andisolating the desired compound.

Compounds of the formulas (1)-(3) where L is carbonyl and T is —O— orwherein L is methylene and T is —O—, are prepared from compounds (4)-(6)using the procedure described by Baker et al., J Org Chem (1988) 53:2340which is incorporated herein by reference. The 2′ or 2′,4″-protectedcompounds of formulas (4)-(6) are first converted to the cycliccarbonates by reaction with carbonyldiimidazole and sodiumhexamethyldisilazide.

Compounds (13)-(15) represent compounds (1)-(3) where L is methylene andT is —O—:

Illustrative Scheme 5 in FIG. 5 illustrates the conversion of thecompound having formula (6) to the compound having the formula (1).FIGS. 11 and 13 illustrate the conversion of erythromycins to ketolides.

In order to prepare compounds of formulas (4)-(6) or (1)-(3) wherein oneof Z and Y is H and the other OH or protected OH or is an aminoderivative as described above, either the carbonyl or oxime orderivatized oxime is reduced using a suitable reducing agent.Substituted amines are obtained by alkylation.

Novel methods of synthesis of the compounds of the invention are alsoprovided.

Exemplary Embodiments

The compounds of formulas (1), (2) and (3) are defined by their varioussubstituents. Table 1 illustrates compounds within the scope of thepresent invention which are:

of formula (1) wherein R_(b) is H, F, Cl, or Br, L is CO, and R_(c) isH;

of formula (2) wherein R_(c) is H and L is CO; and

of formula (3) wherein R_(c) is H, L is CO, and R_(e) is H.

TABLE 1 R_(d) R_(a) Y Z T —CH₃ —CH₂CH₂—φ ═O —NH— —CH═CH₂ —CH₂CH═CH-φ ═O—N(CH₃)— —CH₂CH₂CH₃ —CH₂CH₂NHCH₃ ═NOH —N(NHCH₃)— —CH₃ —CH₂CHOHCH₃═NOCH₂CH₃ —N(OCH₃)— —CH(CH₃)₂ —CH₂—φ H OH —N(N═CH₂)— —CH₃ —CH₂—CH═CH₂ ═O—O— or —NH— —CH₃ —CH₂—CH═CH—(3-quinolyl) ═O —O— or —NH— —CH₃—CH₂—CH₂—CH₂—(3-quinolyl) ═O —O— or —NH— —CH₃—CH₂—CH═CH—(2-methyl-6-quinolyl) ═O —O— or —NH— —CH₃—CH₂—CH═CH—(5-isoquinolyl) ═O —O— or —NH— —CH₃—CH₂—CH═CH—(3-bromo-6-quinolyl) ═O —O— or —NH— —CH₃—CH₂—C═CH—(6-methoxy-2-naphthyl) ═O —O— or —NH— —CH₃—CH₂—C≡C—(2-phenylethenyI) ═O —O— or —NH— —CH₃ —CH₂—C≡C—(3-quinolyl) ═O—O— or —NH— —CH₃ —CH₂—C≡C—naphthyl ═O —O— or —NH— —CH₃—CH₂—C≡C—(6-methyl-2-naphthyl) ═O —O— or —NH— —CH₃—CH₂—C≡C—(3-(2-furanyl)-6-quinolyl) ═O —O— or —NH— —CH═CH₂ —CH₃ ═O —O—or —NH— —CH₂OH —CH₂—C═CH—(4-fluorophenyl) ═O —O— or —NH— —CH₂OH—CH₂—C═CH-(3-quinolyl) ═O —O— or —NH— —CH₂OH —CH₂—C═CH—(6-quinolyl) ═O—O— or —NH— —CH₂OCH₃ —CH₂—C═CH—(3-pyridyl) ═O —O— or —NH— —CH₂CH₂CH₃—CH₂—C═CH—(3-quinolyl) ═O —O— or —NH— —CH₂CH₂CH₃—CH₂—C═CH—(6-chloro-3-quinolyl) ═O —O— or —NH— —CH₂CH₂CH₃—CH₂—C═CH—(4-quinolyl) ═O —O— or —NH— —CH₂CH₂CH₃—CH₂—C═CH—(6-chloro-3-quinolyl) ═O —O— or —NH— —CH₂CH₂CH₃—CH₂—C═CH—(6-hydroxy-3-quinolyl) ═O —O— or —NH— —CH₂CH₂CH₃—CH₂—C═CH—(6-methoxy-3-quinolyl) ═O —O— or —NH— —CH₂CH₂CH₃—CH₂—C═CH—(6-aminocarbonyl-3-quinolyl) ═O —O— or —NH— —CH₂CH₂CH₃—CH₂—C═CH—(3-(2-thiophenyl)-6-quinolyl) ═O —O— or —NH— —CH₂CH₂CH₃—CH₂—C═CH—(6-hydroxy-2-naphthyl) ═O —O— or —NH— —CH₂CH₂CH₃—CH₂—C≡C—(3-quinolyl) ═O —O— or —NH— —CH₂CH₂CH₃—CH₂—C≡C—(6-chIoro-2-naphthyl) ═O —O— or —NH— —CH₂CH₂CH₃—CH₂—C≡C—(6-quinolyl) ═O —O— or —NH— —CH₂CH₂CH₃—CH₂CH₂NHCH₂CH₂—(2-chlorophenyl) ═O —O— or —NH— —CH₃ —CH₂CH₂NH₂ ═O —O—or —NH— —CH₃ OR_(a) replaced by H —NH₂ H —O— or —NH— —CH₃ —CH₃ —NH₂ H—O— or —NH— —CH₃ OR_(a) replaced by H

H —O— or —NH— —CH₃ ″

H —O— or —NH— —CH₃ ″

H —O— or —NH— —CH₃ —CH₂CHClCH₃ H

—O— or —NH— —CH₃ ″ H

—O— or —NH— —CH₃ ″ H

—O— or —NH— —CH₃ —CH₃

H —O— or —NH— —CH₂CH₂CH₃ OR_(a) replaced by H H

—O— or —NH— —CH₂CH₂CH₃ ″ —NH₂ H —O— or —NH— —CH₂CH₂CH₃ —CHCH(OCH₃)CH₃

H —O— or —NH— —CH₂CH₂CH₃ —CH₃ H

—O— or —NH— —CH₂CH₂CH₃ —CH₂CH₂CH₃

H —O— or —NH— —CH₂CH₂CH₃ —CH₂CHBrCH₃ H

—O— or —NH— —CH₃ —CH₂CHOHCH₃ ═NOCHCH₃ —O— or —NH— —CH₂CH₂CH₃ —CH₂CH₂CH₃—NH₂ H —O— or —NH— —CH₃ —CH₂CH═CH₂ ═O —N(CH₃) —CH₃—CH₂CH═CH—(3-quinolyl) ═O —N(CH₃) —CH₃ —CH₂CH═CH₂ ═O N(CH₂CH₂N(CH₃)₂)—CH₃ —CH₂CH═CH—(3-quinolyl) ═O N(CH₂CH₂N(CH₃)₂) —CH₃ —CH₂CH═CH₂ ═ON(CH₂CH═CH₂) —CH₃ —CH₂CH═CH—(3-quinolyl) ═O N(CH₂CH═C—(3-quinolyl)) —CH₃—CH₂CH═CH₂ ═O N(NH₂) —CH₃ —CH₂CH═CH—(3-quinoiyl) ═O N(NH₂) —CH₃—CH₂CH₂CH₂—(3-quinolyl) ═O N(NH₂) —CH₃ —CH₂CH═CH₂ ═O N(NH₂) —CH₃—CH₂CH═CH—(3-quinolyl) ═O N(NH₂) —CH₃ —CH₂CH₂CH₂—(3-quinolyl) ═O N(NH₂)

EXAMPLES

The following examples are intended to illustrate but not to limit theinvention.

Compound numbers and designations are found in the Illustrative Schemesand in the prior disclosure.

In these examples, in the first general step of the method, a6-deoxyerythronolide B (6-dEB) derivative compound is prepared byfermentation of a recombinant Streptomyces host cell.

The fermentation to produce 15-methyl-6-deoxyerythronolide B and14,15-dehydro-6-deoxyerythronolide B requires a synthetic diketideintermediate to be fed to the fermenting cells. The preparation of thesesynthetic diketides is described in Example 1. These synthetic diketidesare substrates for a 6-deoxyerythronolide B synthase (DEBS) that isunable to act on its natural substrate (propionyl CoA) due to a mutationin the ketosynthase domain of module 1 of DEBS. This recombinant DEBS isprovided by plasmid pJRJ2 in Streptomyces coelicolor CH999. S.coelicolor CH999 is described in U.S. Pat. No. 5,672,491, incorporatedherein by reference. A derivative of S. coelicolor CH999, S. coelicolorK39-02, that has been genetically modified to include a ptpA gene, isdescribed in U.S. patent application Ser. No. 09/181,833, incorporatedherein by reference can also be employed for this purpose.

Plasmid pJRJ2 encodes the eryAI, eryAII, and eryAIII genes; the eryAIgene contained in the plasmid contains the KS1 null mutation. The KS1null mutation prevents formation of the 6-deoxyerythronolide B producedby the wild-type gene unless exogenous substrate is provided. PlasmidpJRJ2 and a process for using the plasmid to prepare novel13-substituted erythromycins are described in PCT publication Nos.99/03986 and 97/02358 and in U.S. patent application Ser. Nos.08/675,817, filed Jul. 5, 1996; 08/896,323, filed Jul. 17, 1997; and09/311,756, filed May 14, 1999, each of which is incorporated herein byreference. The exogenous substrates provided can be prepared by themethods and include the compounds described in PCT patent applicationNo. PCT/US00/02397 and U.S. patent application Ser. No. 09/492,733, bothfiled Jan. 27, 2000, by inventors G. Ashley et al., and both of whichclaim priority to U.S. patent application Ser. No. 60/117,384, filedJan. 27, 1999, each of which is incorporated herein by reference. PKSgenes other than the ery genes can also be employed; suitable genesinclude the KS1 null mutation containing oleandolide and megalomicin PKSgenes described in U.S. patent application Ser. Nos. 60/158,305, filedOct. 8, 1999 and 09/428,517, filed Oct. 28, 1999, and PCT applicationNo. US99/24478, filed Oct. 22, 1999, each of which is incorporatedherein by reference.

The fermentation of Streptomyces coelicolor CH999/pJRJ2 and S.coelicolor CH999/pCK7 is described in Example 2. The isolation of the6-deoxyerythronolide products resulting from this fermentation can beachieved by separation.

The isolated products are then added to the fermentation broth ofSaccharopolyspora erythraea strains to make other useful intermediatecompounds of the invention. The S. erythraea strains catalyze thebiosynthesis and attachment of sugar residues to the 3 and 5 positionsof the 6-dEB derivative compounds. These strains also comprise afunctional eryK gene product and so hydroxylate the 6-dEB derivativecompounds at the 12 position. The strains differ in regard to whether afunctional eryF gene product is produced. If so, then the compoundsproduced are hydroxylated at the 6 position as well. If not, then a6-deoxyerythromycin A derivative is produced. These S. erythraeafermentations are described in Example 3, together with the isolation ofthe erythromycin A derivative compounds from the fermentation broth.

The isolated products are then used as intermediates in the chemicalsynthesis of other intermediate compounds of the invention. Forerythromycin A derivative intermediates that comprise a 6-hydroxyl,Examples 4-6 describe the process for alkylating the compounds to makethe 6—O-alkyl intermediates of the invention. The schematic for thesereactions is shown in FIG. 7.

Example 1 Preparation of Diketide Thioesters

The processes used to prepare the N-acetylcysteaminethioesters (NAcS)used to feed the recombinant Streptomyces host cells to make the15-methyl and 14,15-dehydro-6-deoxyerythronolide B intermediatecompounds are described in this Example. The synthesis protocolsdescribed below are also described in U.S. provisional patentapplication Serial No. 60/117,384, filed Jan. 27, 1999, incorporatedherein by reference.

Thus, (2S,3R)-2-methyl-3-hydroxyhexanoate NAcS (Preparation E), which isused to prepare the 15-methyl-6-deoxyerythronolide B intermediate, isprepared from reacting(4S)-N-[(2S,3R)-2-methyl-3-hydroxyhexanoyl]-4-benzyl-2-oxazolidinone(Preparation D) with N-acetylcysteamine (Preparation B).N-acetylcysteamine is, in turn, prepared from N,S-diacetylcysteamine(Preparation A).(4S)-N-[(2S,3R)-2-methyl-3-hydroxyhexanoyl]-4-benzyl-2-oxazolidinone(Preparation D) is prepared from(4S)-N-Propionyl-4-benzyl-2-oxazolidinone (Propionyl-Nox; PreparationC).

In similar fashion, (2S,3R)-2-methyl-3-hydroxy-4-pentenoate NAcS(Preparation G), which is used to prepare the14,15-dehydro-6-deoxyerythronolide B intermediate, is prepared fromreacting(4S)-N-[(2S,3R)-2-methyl-3-hydroxy-4-pentenoyl]-4-benzyl-2-oxazolidinone(Preparation F) with N-acetylcysteamine (Preparation B).(4S)-N-[(2S,3R)-2-methyl-3-hydroxy-4-pentenoyl]-4-benzyl-2-oxazolidinone(Preparation F) is prepared from(4S)-N-Propionyl-4-benzyl-2-oxazolidinone (Propionyl-Nox; PreparationC).

A. N,S-diacetylcysteamine:

Cysteamine hydrochloride (50.0 g) is added to a 1 L 3-neck round bottomflask fitted with a magnetic stir bar, 2 addition funnels, and a pHelectrode. Water (300 mL) is added, and the stirred solution is cooledon ice. The pH is adjusted to 8.0 by addition of 8 N KOH. Aceticanhydride (125 mL) is placed in one addition funnel, and 8N KOH (350 mL)is placed in the other addition funnel. The acetic anhydride is addeddropwise to the cysteamine solution, with 8 N KOH being added so as tokeep the reaction pH at 8+/−1. After addition of acetic anhydride iscomplete, the pH was adjusted to 7.0 using 1 N HCl and the mixture isallowed to stir for 75 min. on ice. Solid NaCl is added to saturation,and the solution is extracted 4 times using 400 mL portions of CH₂Cl₂.The organic extracts are combined, dried over MgSO₄, filtered, andconcentrated under reduced pressure to yield 68.9 g (97% yield) of apale yellow oil, which crystallizes upon standing at 4° C.

B. N-acetylcysteamine:

N,S-diacetylcysteamine (42.64 g) is placed in a 2 L round bottom flaskfitted with a magnetic stirrer, and dissolved in 1400 mL of water. Theflask is purged with N₂, and the mixture is chilled in an ice bath.Potassium hydroxide (49.42 g) is added, and the mixture is stirred for 2hr. on ice under inert atmosphere. The pH is adjusted to 7 using 6 NHCl, and solid NaCl is added to saturation. The mixture is extracted 7times with 500 mL portions of CH₂Cl₂. The organic extracts are combined,dried over MgSO₄, filtered, and concentrated under reduced pressure toyield 30.2 g (96% yield) of product. This material is distilledimmediately prior to use, bp 138-140° C./7 mmHg.

C. (4S)-N-propionyl-4-benzyl-2-oxazolidinone (Propionyl-NOx):

A dry, 1 L three-necked round bottomed flask equipped with a 500 mLaddition funnel and a stir bar was charged with 20 g of(4S)-4-benzyl-2-oxazolidinone, capped with septa and flushed withnitrogen. Anhydrous THF (300 mL) was added by cannula and the resultingsolution was cooled with a −78° C bath of dry ice/isopropanol. Theaddition funnel was charged with 78 mL of n-butyllithium (1.6 M inhexane) by cannula, which was added in a slow stream to the reaction.Distilled propionyl chloride (bp 77-79° C.), 8.0 mL, was added rapidlyvia syringe. The reaction was allowed to stir for 30 min. in the dryice/isopropanol bath.

The reaction was removed from the cold bath, allowed to warm to >0° C.,and quenched with 50 mL of saturated aqueous NH₄Cl. The mixture wasconcentrated to a slurry on a rotary evaporator. The slurry wasextracted three times with 250 mL portions of ethyl ether. The organicextracts were combined and washed with 50 mL each of saturated aqueousNaHCO₃ and brine, dried with MgSO₄, filtered, and concentrated to give ayellow oil. The material crystallized upon sitting. The crystals weretriturated once with cold (−20° C.) hexanes to give 21.0 g (80% yield)of white crystalline material, m.p. 41-43° C.

APCI-MS: m/z=234 (MH+), 178, 117. 1H-NMR (360 MHz, CDCl₃): δ7.2-7.4(5H,m); 4.67 (1H,m,H4); 4.14-4.22 (2H,m,H5); 3.30 (1H,dd,J=3,13Hz,benzylic); 2.89-3.03 (2H,m,H2′); 2.77 (1H,dd,J=9,13,benzylic); 1.20(3H,t,J=7 Hz,H2′).

D. (4S)-N-[(2S,3R)-2-methyl-3-hydroxyhexanoyl]-4-benzyl-2-oxazolidinone:

A dry, 2 L three-necked round bottomed flask equipped with a 500 mLaddition funnel, a low-temperature thermometer, and a stir bar wascharged with 19.84 g of N-propionyl-oxazolidinone, capped with septa andflushed with nitrogen. Anhydrous dichloromethane (100 mL) was added bycannula, and the resulting solution was cooled to −65° C. in a bath ofdry ice/isopropanol. The addition funnel was charged by cannula with 100mL of dibutylboron triflate (1.0 M in dichloromethane), which was addedin a slow stream to the reaction. Triethylamine (15.6 mL) was addeddropwise by syringe, keeping the reaction temperature below −10° C. Thereaction was then transferred to an ice bath and allowed to stir at 0°C. for 30 min. After that period, the reaction was placed back into thedry ice/isopropanol bath and allowed to cool to −65° C. Butyraldehyde(8.6 mL) was added rapidly by syringe, and the reaction was allowed tostir for 30 min.

The reaction was transferred to an ice bath and the addition funnel wascharged with 100 mL of a 1 M aqueous phosphate solution, pH 7.0 (thephosphate solution is comprised of equal molar amounts of mono- anddibasic potassium phosphate). The phosphate solution was added asquickly as possible while keeping the reaction temperature below 10° C.The addition funnel was then charged with 300 mL methanol which wasadded as quickly as possible while keeping the reaction temperaturebelow 10° C. Finally, the addition funnel was charged with 300 mL of 2:1methanol: 30% hydrogen peroxide. This was added dropwise to ensure thatthe temperature was kept below 10° C. The reaction was stirred for onehr. after completion of addition. The solvent was then removed on arotary evaporator until a slurry remained. The slurry was extracted 4times with 500 mL portions of ethyl ether. The combined organic extractswere washed with 250 mL each of saturated aqueous sodium bicarbonate andbrine. The extract was then dried with MgSO₄, filtered, and concentratedto give a slightly yellow oil. The material was then chromatographed onSiO₂ using 2:1 hexanes:ethyl acetate (product R_(f)=0.4) resulting in22.0 g (85% yield) of title compound as a colorless oil.

APCI-MS: m/z 306 (MH+); 1H-NMR (360 MHz, CDCl₃): δ7.2-7.4 (5H,m,phenyl);4.71 (1H,m,H4); 4.17-4.25 (2H,m,H5); 3.96 (1H,m,H3′); 3.77(1H,dq,J=2.5,7 Hz, H2′); 3.26 (1H,dd,J=4,13 Hz,benzylic); 2.79(1H,dd,J=9,13 Hz,benzylic); 1.5-1.6 (2H,m,H4′); 1.3-1.5 (2H,m,H5′); 1.27(3H,d,J=7 Hz,2′-Me); 0.94 (3H,t,J=7 Hz,H6′).

E. (2S,3R)-2-methyl-3-hydroxyhexanoate N-acetylcysteamine Thioester:

N-acetylcysteamine was distilled at 130° C./7 mm Hg to give a colorlessliquid at room temperature. A dry, 1 L three-necked round bottomed flaskequipped with a 500 mL addition funnel and a stir bar was capped withsepta and flushed with nitrogen. The flask was then charged with 10.7 mLof N-acetylcysteamine by syringe and with 400 mL of 15 anhydrous THF bycannula. The mixture was cooled with a MeOH/ice bath. Butyllithium (64mL of 1.6 M in hexanes) was added dropwise by syringe, resulting information of a white precipitate. After stirring for 30 min.,trimethylaluminum (51 mL of 2.0 M in hexanes) was added dropwise bysyringe. The reaction became clear after addition of trimethylaluminumand was allowed to stir an additional 30 min. During this period, 20.5 g(0.068 mol) of(4S)-N-[(2S,3R)-2-methyl-3-hydroxylhexanoyl]-4-benzyl-2-oxazolidinonewas put under a blanket of nitrogen and dissolved in 100 mL of anhydrousTHF; this solution was then transferred in a slow stream by cannula intothe reaction. The resulting reaction mixture turned a yellow-green colorand was allowed to stir for 1 hr. The reaction was finished when thestarting material could no longer be seen by thin-layer chromatographicanalysis (ca. 1 hr.).

The reaction was treated with enough saturated oxalic acid to give aneutral reaction with pH paper (approximately 90 mL). The solvents werethen removed on a rotary evaporator to give a white slurry. The slurrywas extracted six times with 250 mL portions of ethyl ether. The organicextracts were combined and washed with brine, dried with MgSO₄,filtered, and concentrated to give a slightly yellow oil. The thioesterproduct was purified by flash chromatography on SiO₂ using 1:1hexanes:EtOAc until the elution of 4-benzyl-2-oxazolidinone. At thatpoint, the solvent system was switched to 100% EtOAc to give purefractions of diketide thioester. The product fractions were combined andconcentrated to give 14.9 g (89% yield) of title compound. This compoundis referred to as the propyl diketide thioester in Example 2.

APCI-MS: m/z 248 (MH+); 1H-NMR (360 MHz, CDCl₃): δ5.8 (br s,1H); 3.94(dt,1H), 3.46 (m,2H), 3.03 (dt,2H), 2.71 (dq,1H), 1.97 (s,3H), 1.50(m,2H), 1.37 (M,2H), 1.21 (d,3H), 0.94 (t,3H).

F.(4S)-N-[(2S,3R)-2-methyl-3-hydroxy-4-pentenoyl]-4-benzyl-2-oxazolidinone:

A dry, 2 L three-necked round bottomed flask equipped with a 500 mLaddition funnel, a low-temperature thermometer, and a stir bar wascharged with 20.0 g of propionyl oxazolidinone A, capped with septa andflushed with nitrogen. Anhydrous dichloromethane (100 ml) was added andthe resulting solution was cooled to −15° C. in a bath of methanol/ice.Dibutylboron triflate (100 mL of 1.0 M in dichloromethane) was added ina slow stream via the addition funnel at such a rate as to keep thereaction temperature below 3° C. Diisopropylethylamine (17.9 mL) wasadded dropwise by syringe, again keeping the internal temperature below3° C. The reaction was then cooled to −65° C. using a dryice/isopropanol bath. Acrolein was added over 5 min. by syringe. Thereaction was allowed to stir for 30 min. after completion of addition.

The reaction was then transferred to an ice bath and the addition funnelwas charged with 120 mL (0.1 mol) of a 1 M aqueous phosphate solution,pH 7.0 (the phosphate solution is comprised of equal molar amounts ofmono- and dibasic phosphate). The phosphate solution was added asquickly as possible while keeping the reaction temperature below 10° C.The addition funnel was then charged with 400 mL of methanol that wereadded as quickly as possible while keeping the reaction temperaturebelow 10° C. Finally, the addition funnel was charged with 400 mL of 2:1methanol:30% hydrogen peroxide by initial dropwise addition to keep thetemperature below 10° C. The reaction was stirred for one hour. Thesolvent was removed using a rotary evaporator, leaving a slurry. Theslurry was extracted 4 times with 500 mL portions of ethyl ether. Theorganic extracts were combined and washed with 250 mL each of saturatedsodium bicarbonate and brine, then dried with MgSO₄, filtered, andconcentrated to give a slightly yellow oil. Trituration with hexaneinduced crystallization. Recrystallization from ether by addition ofhexane resulted in 13.67 g (55% yield) of product.

1H-NMR (360 MHz, CDCl₃): δ7.2-7.4 (m,5H); 5.86 (ddd,1H), 5.35 (dt,1H),5.22 (dt,1H), 4.71 (m,1H), 4.51 (m,1H), 4.21 (m,2H), 3.89 (dq,1H), 3.26(dd,1H), 2.80 (dd,1H), 1.25 (d,3H).

G. (2S,3R)-2-methyl-3-hydroxy-4-pentenoate N-acetylcysteamine Thioester:

N-acetylcysteamine was distilled at 130° C./7 mm Hg to give a colorlessliquid at room temperature. A dry, 1 L three-necked round bottomed flaskequipped with a 500 mL addition funnel and a stir bar was capped withsepta and flushed with nitrogen. The flask was then charged with 7.5 mLof N-acetylcysteamine by syringe and with 500 mL of anhydrous THF bycannula. The reaction was then cooled with a MeOH/ice bath. Butyllithium(44 mL of 1.6 M in hexane) was added dropwise by syringe. A whiteprecipitate formed as the n-BuLi was added. After stirring for 30 min.,35.5 mL (0.071 mol) of trimethylaluminum (2.0 M in hexane) were addeddrop-wise by syringe. The reaction became clear after addition oftrimethylaluminum and was allowed to stir an additional 30 min.(4S)-N-[(2S,3R)-2-methyl-3-hydroxy-4-pentenoyl]-4-benzyl-2-oxazolidinonefrom Preparation F (13.6 g) was put under a blanket of nitrogen,dissolved in 50 mL of anhydrous THF, and this solution was thentransferred in a slow stream by cannula into the reaction. The resultingreaction mixture turned a yellow-green color and was allowed to stir for1 hr. The reaction was judged to be finished when starting materialcould no longer be seen by thin-layer chromatography (ca. 30 min.).

Enough saturated oxalic acid was added to give a neutral reaction withpH paper (approximately 60 mL). The solvents were then removed by rotaryevaporator to give a white slurry. The slurry was extracted six timeswith 250 mL portions of ethyl ether. The organic extracts were combined,washed with brine, dried with MgSO₄, filtered, and concentrated to givea slightly yellow oil. The thioester was then purified by flashchromatography on SiO₂. The column was run with 1:1 hexanes:ethylacetate until the elution of oxazolidinone. At that point, the eluentwas switched to 100% ethyl acetate to give pure fractions of product.The fractions were combined and concentrated to give 7.7 g (71% yield)of title compound product. This product is referred to as the vinyldiketide thioester in Example 2.

1H-NMR (360 MHz, CDCl₃): δ5.82 (ddd,1H), 5.78 (br s, 1H), 5.32 (dt,1H),5.21 (dt,1H), 4.47 (m,1H), 3.45 (m,2H), 3.04 (m,2H), 2.81 (dq,1H), 1.96(s,3H), 1.22 (d,3H).

Example 2 Preparation of Erythronolide

A. 15-methyl-6-deoxyerythronolide B (Compound P, R_(d)=propyl):

Streptomyces coelicolor CH999/pJRJ2 is described in U.S. patentapplication Ser. Nos. 08/896,323, filed Jul. 17, 1997, and 08/675,817,filed Jul. 5, 1996, each of which is incorporated herein by reference.Plasmid pJRJ2 encodes a mutated form of DEBS in which the ketosynthasedomain of module 1 (KS1) has been inactivated via mutagenesis (KS1°). S.coelicolor strains comprising this plasmid that are fed (2S,3R)-2-methyl-3-hydroxyhexanoate-N-acetylcysteamine Preparation E, propyldiketide) of Example 1 produce 15-methyl-6-deoxyerythronolide B.

A 1 mL vial of the CH999/pJRJ2 working cell bank is thawed and thecontents of the vial are added to 50 mL of Inoculum Medium 1 in a 250 mLbaffled flask. The flask is placed in an incubator/shaker maintained at30±1° C. and 175±25 RPM for 48±10 hours. The 50 mL culture is then addedto a 2.8 L baffled flask containing 500 mL of Inoculum Medium 1. Thisflask is incubated in an incubator/shaker at 30±1° C. and 175±25 RPM for48±10 hours. The 500 mL culture is divided equally among ten 2.8 Lbaffled flasks each containing 500 mL of Inoculum Medium 1. All flasksare then incubated as described previously.

A 150 L fermenter is prepared by sterilizing 100 L of Production Medium1 at 121° C. for 45 minutes. After incubation, all 10 flasks arecombined in a 5 L sterile inoculation bottle and aseptically added to a150 L fermenter. The fermenter is controlled at 30° C., pH 6.5 byaddition of 2.5 N H₂SO₄ and 2.5 N NaOH, dissolved oxygen ≧80% airsaturation by agitation rate (500-700 RPM), air flow rate (10-50 LPM),and/or back pressure control (0.1-0.4 bar). Foam is controlled by theintermittent addition of a 50% solution of Antifoam B.

At 24±5 hours (2S, 3R)-2-methyl-3-hydroxyhexanoyl-N-acetylcysteamine(propyl diketide, Preparation E in Example 1) is added to a finalconcentration of 1 g/L. Propyl diketide is prepared by solubolizing indimethyl sulfoxide at a ratio of 1:4 (diketide to DMSO) and then filtersterilized (0.2 μm, nylon filter). Production of15-methyl-6-deoxyerythonolide B (15-methyl-6dEB) ceases on day 7 and thefermenter is harvested. The fermentation broth is centrifuged at 20,500g in an Alpha Laval AS-26 centrifuge. The product is predominantly inthe centrate; the centrifuged cell mass is discarded.

This process has also been completed in a 1000 L fermenter (700 Lworking volume). The inoculum process is identical to the above processexcept that the 150 L fermenter is charged with Inoculum Medium 1 andthe 1000 L fermenter is charged with Production Medium 1. The fermenteris controlled at 30° C., pH 6.5 by addition of 2.5-5 N H₂SO₄ and 2.5-5 NNaOH, dissolved oxygen ≧70% air saturation by agitation rate (140-205RPM), air flow rate (100-200 LPM), and/or back pressure control (0.2-0.5bar). Foam is controlled by the addition of a 50% solution of Antifoam Bas needed. At 24±5 hours racemic2-methyl-3-hydroxyhexanoyl-N-propionylcysteamine (300 grams) is added tothe 1000 L fermenter. The fermenter is harvested at 4.6 days bycentrifugation as described above.

Media used in this process include the following:

Inoculum Medium 1

Component Concentration KNO₃ 2 g/L Yeast extract 20 g/L Hycase SF 20 g/LFeSO₄—7H₂O 25 mg/L NaCl₄ (12.5% stock) 4 mL/L MgSO₄ (12.5% stock) 4 mL/LMnSO₄—H₂O (0.5% stock) 1 mL/L ZnSO₄—7H₂O (1.0% stock) 1 mL/L CaCl₂—2H₂O2.0% stock 1 mL/L

Sterilized by autoclaving for 60 minutes at 121° C.

Post-sterile additions:

1) 1 mL/L of 50 mg/ml Thiostrepton in 100% DMSO, sterile filtered.

2) 1 mL/L 100% Antifoam B silicon emulsion (J. T. Baker), autoclaved.

3) 40 mL of 500 g/L glucose, sterile filtered.

Production Medium 1

Component g/L Corn Starch 45 Corn steep liquor 10 Dried, inactivatedbrewers yeast 10 CaCO₃  1

Sterilized in fermenter for 45 minutes at 121° C.

Post-sterile additions for Production Medium 1:

1) 1 mL of 50 mg/ml Thiostrepton in 100% DMSO, sterile filtered.

2) 1 mL/L of 100% Antifoam B (J. T. Baker), autoclaved.

After centrifugation, the centrate is filtered. The filtrate(approximately 700 L) are passed through an Amicon Moduline column(20×350 cm) containing 20 L of HP20 resin (Mitsubishi). The flow rateduring loading is 4 L/minute with a pressure drop below 8 psi. Afterloading the resin is washed with 20 L of water and then 40 L of 30%methanol. 15-methyl-6dEB is eluted using 100% methanol. Four 12 Lfractions were collected with fractions 2, 3 and 4 containing all of thedetectable 15-methyl-6dEB. The 15-methyl-6dEB product pool is dilutedwith 36.7 L of water giving 75 L of a clear solution. This solution isloaded directly onto a 5 L Amicon Vantage Column containing HP20SS resin(Mitsubishi). Column loading is carried out at 1 L/minute. The column iseluted with 20 L of 65% methanol, 20 L of 70% methanol, 20 L of 80%methanol, and finally 20 L of 100% methanol. A total of 16×5 L fractionswere collected. The 80% fractions along with the last 70% fraction werecombined (25 L) and evaporated to dryness. The resulting residue isdissolved in 1 L of 100% methanol, filtered, evaporated, and dried in avacuum oven at 40° C. This process resulted in 33 g of a solid productcontaining 93% 15-methyl-6dEB.

B. 14,15-dehydro-6-deoxyerythronolide B (Compound P, R_(d)=vinyl):

S. coelicolor strains comprising this plasmid that are fed(2S,3R)-2-methyl-3-hydroxy-4-pentenoate NAc Cysteamine thioester(Preparation G) of Example 1 produce 14,15-dehydro-6-deoxyerythronolideB when prepared in accordance with the process described in PreparationA above to produce 15-methyl-6-deoxyerythronolide B.

C. 14-nor-6-deoxyerythronolide B (Compound P, R_(d)=methyl):

Similarly, 14-nor-6-deoxyerythronolide B is produced using S. coelicolorCH999/pCK7 host, when prepared in accordance with the process describedin Example 2A

Example 3 Preparation of Erythromycins

The 6-dEB derivative compounds produced in Example 2, Preparations A—Care converted to erythromycin derivatives using a recombinant strain ofSaccharopolyspora erythraea. For production of erythromycins having boththe 6- and 12-hydroxyl groups, the S. erythraes strain used was K40-67or K39-14V. This strain was created by transforming an S. erythraestrain capable of producing high levels of erythromycin A with apWHM3-derived plasmid comprising a mutated eryAl sequence encoding aninactivated KS1 domain. By homologous recombination, the resultingtransformants were rendered incapable of producing 6-deoxyerythronolideB. Thus the dEB analog fed is not subject to competition forhydroxylation at the 6-position. For production of erythromycinderivatives having only the 12-hydroxyl group, the S. erythrae strainused was K39-07. This strain was constructed from strain K40-67 bydisruption of the eryF hydroxylase gene; this destroys ability tohydroxylate the analog at the 6-position. Both strains were fermentedunder substantially similar conditions, as described below.

15-methyl-erythromycin A: 15-methyl-erythromycin A is produced accordingto the following protocol: A 1 mL vial of the K39-14V working cell bankis thawed and the contents of the vial are added to 50 mL of InoculumMedium 2 in a 250 mL baffled flask. The flask is placed in anincubator/shaker maintained at 34±1° C. and 175±25 RPM for 48±10 hours.The 50 mL culture is then added to a 2.8 L baffled flask containing 500mL of Inoculum Medium 2. The flask is incubated in an incubator/shakerat 34±1° C. and 175±25 RPM for 48±10 hours. The 500 mL culture isdivided equally among ten 2.8 L baffled flasks each containing 500 mL ofInoculum Medium 2. All flasks are then incubated as describedpreviously.

A 150 L fermenter is prepared by sterilizing 100 L of Production Medium2 at 121° C. for 45 minutes. After incubation, all 10 flasks arecombined in a 5 L sterile inoculation bottle and aseptically added to a150 L fermenter. The fermenter is controlled at 34° C., pH 7.0 byaddition of 2.5 N H₂SO₄ and 2.5 N NaOH, dissolved oxygen ≧80% airsaturation by agitation rate (500-700 RPM), air flow rate (15-50 LPM),and/or back pressure control (0.1-0.4 bar). Foam is controlled by theaddition of a 50% solution of Antifoam B.

At 24±5 hours a 58-60 mL/hour 15% dextrin (w/v) feed is initiated. Thedextrin solution is continuously mixed during the feed period. At 24±5hours 25 grams of 15-methyl-6dEB (Preparation A in Example 2) are addedto the fermenter. The 15-methyl-6dEB is prepared by solubolizing 25grams of 15-methyl-6dEB in 400-600 mL of 100% ethanol and filtering (0.2μm, nylon filter). Conversion of 15-methyl-6dEB to15-methyl-erythromycin A ceases after 60±10 hours and the fermenter isharvested. The fermentation broth is centrifuged at 20,500 g in an AlphaLaval AS-26 centrifuge. The product is predominantly in the centrate;the centrifuged cell mass is discarded.

Media used in this process include the following:

Inoculum Medium 2

Component g/L Corn Starch 16.0  Corn dextrin 10.0  Soy Meal Flour 15.0 CaCO₃ 4.0 Corn steep liquor 5.0 Soy Bean Oil 6.0 NaCl 2.5 (NH₄)₂SO₄ 1.0

Sterilized by autoclaving for 60 minutes at 121° C.

Post-sterile addition:

1 mL/L 100% Antifoam B (J. T. Baker), autoclaved.

Production Medium 2

Component g/L Corn Starch 17.5  Corn Dextrin (Type 3) 16.0  Soy MealFlour 16.5  CaCO₃ 4.0 Corn steep liquor 6.0 Soy Bean Oil 3.0 NaCl 3.5(NH₄)₂SO₄ 1.0

Sterilized in fermenter for 45 minutes at 121° C.

Centrifuged fermentation broth (127 L) containing 34 g of the targetmolecule is passed through 18.3 L of HP20 sorbent packed into an AmiconP350 Moduline 2 chromatography column. At 4 L/min loading, backpressureis found to be less than 5 psi. Following loading, the resin is washedwith 20 L deionized water and then 40 L of 30% methanol.15-Methyl-Erythromycin A is eluted using 54 L of 100% methanol. Theproduct pool is evaporated using a Buchi rotary evaporator (R-152). Thesolids were dissolved in a minimal amount of 100% methanol, filtered andthe filtrate evaporated to dryness. This resulted in 123 g of materialcontaining 30% 15-Methyl-Erythromycin A by weight. 80 grams of the 30%material is extracted twice with 1 L of 40° C. acetone. The acetoneextract is filtered, and the filtrate is dried on the inside surface ofa 20 L rotary evaporation flask. The solids were extracted with 9:1hexane to acetone three times at 40° C. The organic extracts were pooledand evaporated to dryness giving 32 g of solids enriched (68%) in15-Methyl-Erythromycin A. The product pool from the acetone/hexaneextraction is dissolved in 1 L of methanol to which an equal amount ofwater is added. The methanol solution is loaded onto a HP20SSchromatography column (Kontes) previously washed and equilibrated with50% methanol. Column dimensions were 4.8×115 cm. Column loading withrespect to 15-Methyl-Erythromycin A is 11 g/L. The column is washed with50% (0.8 L) and 60% (8 L) methanol in water. Elution of the targetmolecule is carried out using 70% (8L), 80% (16 L) and 85% (8 L)methanol in water. 1 L fractions were collected. Fractions 11-29 werecombined, evaporated and dried in a vacuum oven giving 23 g of productwith 93% purity.

This material served as starting material for the chemicalderivatization procedures described in the following examples. Thefollowing compounds are also produced by this methodology: (i)14-norerythromycin A (R_(d)=Me); (ii) 14,15-dehydro-erythromycin A(R_(d)=—CH═CH₂); (iii) 14-nor-6-deoxy-etythromycin A; (iv)14,15-dehydro-6-deoxy-erythromycin A; and (v)15-methyl-6-deoxy-erythromycin A. When used to make3-descladinose-3-oxo-derivatives, the erythromycin A derivatives werenot separated from the erythromycin C derivatives; instead, mixtures ofthe erythromycin A and erythromycin C compounds were used as startingmaterials for chemical derivatization.

These products were extracted and purified as follows:

In general, fermentation broths are brought to pH 8.0 by addition ofNaOH and ethanol is added (0.1 L/L broth). The broth is clarified bycentrifugation and loaded onto an XAD-16 resin (Rohm and Haas) column (1kg XAD/1 g erythromycin analogs) at a flow rate of 2-4 mL/cm²-min. Theloaded resin is washed with 2 column volumes of 20% (v/v) ethanol inwater and the erythromycin analogs are eluted from the resin withacetone and collected in ½ column volume fractions. The fractionscontaining erythromycin analogs are identified by thin-layerchromatography (ethyl acetate:hexanes 1:1) and HPLC/NS.

The acetone fractions containing erythromycin analogs are pooled and thevolatiles are removed under reduced pressure. The resulting aqueousmixture is extracted with ethyl acetate. The ethyl acetate extract iswashed with saturated NaH₂CO₃ and brine solutions, dried over sodium ormagnesium sulfate, filtered, and concentrated to dryness under reducedpressure. Crude material is dissolved in dichloromethane and loaded ontoa pad of silica gel and washed with dichloromethane:methanol (96:4 v/v)until the eluent is no longer yellow. The desired material is withdichloromethane:methanol:triethylamine (94:4:2 v/v) and collected infractions. Fractions containing erythromycin are identified bythin-layer chromatography, collected and concentrated under reducedpressure. This material is recrystallized from dichloromethane/hexanes.

This general procedure is illustrated as follows:

(i) 14-norerythromycins: 1 liter of ethanol was added to each of 10liters of fermention broth. The broth was centrifuged and thesupernatant was passed through 0.6 liters of XAD (column dimensions 17cm×6.5) cm at a flow rate of 100 mL/min. After loading, the column waswashed with 1.5 liters of 20% (v/v) ethanol in water. The desiredmaterial was then eluted with acetone. The fractions containing thismaterial were concentrated under reduced pressure until the volatileswere removed and the aqueous remainder was extracted with ethyl acetate.The ethyl acetate layers were washed with saturated sodium bicarbonatesolution, brine, dried with magnesium sulfate and concentrated underreduced pressure to give the crude extract.

Crude material (0.6 g) was dissolved in dichloromethane and gravityfiltered through a 3 cm pad of silica gel in a 6 cm diameter flittedfunnel. The material was eluted with 400 mL of dichloromethane followedby 400 mL dichloromethane:methanol:triethylamine (90:10:2 v/v) andcollected in 40 mL fractions.

Fractions containing erythromycin were identified by thin-layerchromatography (ether:methanol:NH₄OH 90:8:2 v/v, R_(f)˜0.35 anddichloromethane:methanol 95:5 v/v, R_(f)˜0) and concentrated underreduced pressure. This material was recrystallized fromdichloromethane/hexanes.

(ii) 15-methyl-erythromycin A: 8 liters of ethanol was added toapproximately 80 liters of fermention broth. The broth was centrifugedand the supernatant was passed through 2.5 liters of XAD at a flow rateof 230 mL/min. After loading the column was washed with 1 liter of waterand 5 liters of 20% (v/v) ethanol in water. The desired material wasthen eluted with acetone. The fractions containing this material wereconcentrated under reduced pressure until the volatiles were removed andthe aqueous remainder was extracted with ethyl acetate. The ethylacetate layers were washed with saturated sodium bicarbonate solution,brine, dried with magnesium sulfate and concentrated under reducedpressure to give the crude extract

Crude material (8.3 g) was dissolved in dichloromethane and gravityfiltered through a 3 cm pad of silica gel in a 9 cm diameter frittedfunnel. The material was eluted with 200 mL of dichloromethane followedby 600 mL of dichloromethane:methanol (96:4 v/v) followed by 900 mLdichloromethane:methanol:triethylamine (89:9:2 v/v) and collected in 40mL fractions. Fractions containing erythromycin were identified bythin-layer chromatography (ether:methanol:NH₄OH 90:8:2 v/v, R_(f)˜0.4and dichloromethane:methanol 95:5, R_(f)˜0.05) and concentrated underreduced pressure.

This material was re-subjected to the above procedure before it wassuitable for recrystallization.

(iii) 14-nor-6-deoxy-erythromycins: 1 liter of ethanol was added to eachof 210 liter fermentions. The broths were centrifuged and thesupernatants were combined for a total of approximately 22 liters. Thecombined broths were then passed through 1 liter of XAD (columndimensions 23.5 cm×6.5 cm (i.d.) at a flow rate of 170 mL/min. Afterloading the column was washed with 2 liters of 20% (v/v) ethanol inwater. The desired material was then eluted with acetone. The fractionscontaining this material were concentrated under reduced pressure untilthe volitiles were removed and the aqueous remainder was extracted withethyl acetate. The ethyl acetate layers were washed with saturatedsodium bicarbonate solution, brine, dried with magnesium sulfate andconcentrated under reduced pressure to give the crude extract.

(iv) 15-methyl-6-deoxy-erythromycins: 1 liter of ethanol was added toeach of 3 fermentors containing 10 liters of broth. The broths werecentrifuged and the supernatant was passed over 1.25 liters of XAD(column dimensions 40 cm×6.5 cm) at a flow rate of 130 mL/min. Thecolumn was then washed with 3 liters of 20% (v/v) ethanol in water. Thedesired material was then eluted with acetone. The fractions containingthis material were concentrated under reduced pressure until thevolitiles were removed and the aqueous remainder was extracted withethyl acetate. The ethyl acetate layers were washed with saturatedsodium bicarbonate solution, brine, dried with magnesium sulfate andconcentrated under reduced pressure to give the crude extract.

Crude material (2.8 g) was dissolved in dichloromethane and gravityfiltered through a 3 cm pad of silica gel in a 6 cm diameter frittedfunnel. The material was eluted with 400 mL of dichloromethane:methanol(96:4 v/v) followed by 400 mL dichloromethane:methanol:triethylamine(89:9:2 v/v) and collected in 40 mL fractions. Fractions containingerythromycin were identified by thin-layer chromatography(ether:methanol:NH₄OH 90:8:2 v/v and dichloromethane:methanol 95:5) andconcentrated under reduced pressure. This material required furtherpurification by silica gel chromatography.

Example 4 Synthesis of 6-O-methyl-14-norerythromycin A i.e., Formula (4)where R_(d)=Me, R_(d)=Me, R_(c)=H, R_(e)=H

A. 14-Norerythromycin A 9-Oxime:

A solution of 14-norerythromycin A (0.621 g, 80% pure), hydroxylamine(0.5 ml of 50% aqueous solution) and acetic acid (0.2 ml) in isopropanol(2 ml) was kept at 50° C. for 22 hours. It was extracted withchloroform/ethanol (3/2), washed with sodium bicarbonate, brine, anddried over MgSO₄. Filtration and evaporation in vacuo yielded a crudeproduct (0.65 g) as a white solid which was used directly for nexttransformation.

B. 14-Norerythromycin A-9-[O-(1-isopropoxycyclohexyl)]oxime:

To a solution of above crude 14-norerythromycin A 9-oxime (0.65 g) and1,1-diisopropoxy-cyclohexanone (0.95 ml) in methylene chloride (2 ml)was added pyridinium p-toluenesulfonate (PPTS) (0.333 g) in methylenechloride (2 ml). After stirring overnight, the mixture was extracted(chloroform/ethanol 3:2), washed (NaHCO₃—H₂O, brine), and dried (MgSO₄).After filtration and evaporation in vacuo, the crude product wasrepeatedly driven with toluene and isopropanol to yield 0.74 g ofproduct, which was used directly for next reaction.

C. 2′,4″-bis-O-trimethylsilyl-14-norerythromycinA-9-[O-(1-isopropoxycyclohexyl)]oxime:

To a solution of 14-norerythromycinA-9-[O-(1-isopropoxycyclohexyl)]oxime (0.74 g) in methylene chloride (6ml) was added a solution of trimethylsilyl imidazole (0.33 ml) andtrimethylsilyl chloride (0.18 ml) in methylene chloride (2 ml) at 0° C.After 5 minute stirring, ethyl acetate was added, washed (NaHCO₃—H₂O,brine), and dried (MgSO₄). Flash chromatography on silica gel (10:1hexanes:acetone, 1% triethylamine) afforded pure product as a whitesolid (0.50 g). Mass spectrometry reveals [M+H]⁺=1020.

D. 6-O-Methyl-2′,4″-bis-O-trimethylsilyl-14-norerythromycinA-9-[O-(1-isopropoxycyclohexyl)]oxime:

A solution of 2′,4″-bis-O-trimethylsilyl-14-norerythromycin A9-[O-(1-isopropoxycyclohexyl)]oxime (0.3 g, 0.29 mmol) in 1:1methylsuylfoxide/tetrahydrofuran (DMSO/THF) (1.4 ml) was treated with0.3 ml of a 2 M solution of methyl bromide in ether and cooled to 10° C.A mixture of 1 M solution of potassium tert-butoxide in THF (0.6 ml) andDMSO (0.6 ml) was added over 6 hours using a syringe pump. The reactionwas then diluted with ethyl acetate, washed with saturated NaHCO₃,brine, and dried over MgSO₄. Filtration and evaporation in vacuo yieldeda crude product (0.29 g) as a white solid. Mass spectrometry reveals[M+H]⁺=1034.

E. 6-O-Methyl-14-norerythromycin A 9-oxime:

A mixture of 6-O-methyl-2′,4″-bis-O-trimethylsilyl-14-norerythromycin A9-[O-(1-isopropoxycyclohexyl)]oxime (0.29 g), acetic acid (3.6 ml),acetonitrile (6 ml) and water (3 ml) was stirred at ambient temperaturefor 4.5 hours. The mixture was driven to dryness using toluene to give acrude product as white solid (0.24 g), which was used directly for nextstep without further purification.

F. 6-O-Methyl-14-norerythromycin A:

A mixture of6-O-methyl-14-norerythromycin A 9-oxime (0.24 g), sodiumhydrosulfite (0.45 g, 85% pure), water (3 ml), ethanol (3 ml) and formicacid (0.07 ml) was kept at 85° C. for 8 hours. The reaction was broughtto pH 8 with 1 N NaOH and extracted with ethyl acetate. The organicextract was washed with brine, dried over MgSO₄, filtered, andconcentrated to yield a crude product as a white solid (0.2 g). Massspectrometry reveals [M+H]⁺=735.

Example 5 Synthesis of 6-O-methyl-14,15-dehydroerythromycin A, i.e.Formula (4) where R_(d)=CH═CH₂, R_(a)=Me, R_(c)=H, R_(e)=H

A. 14,15-dehydroerythromycin A 9-oxime

A suspension of 14,15-dehydroerythromycin A (1.984 g, 47% purity, 1.2mmol) in 6 mL of 2-propanol was treated with 1.97 mL of 50% aqueoushydroxylamine and stirred until dissolved. Acetic acid (0.62 mL) wasadded and the mixture was stirred for 25 hours at 50° C. Upon cooling toambient temperature, saturated NaHCO₃ was added and the mixture wasconcentrated en vacuo to remove isopropanol. The resulting aqueousmixture was extracted three times with 250-mL portions of CHCl₃. Theorganic extracts were combined, washed with saturated NaHCO₃, water, andbrine, then dried over MgSO₄, filtered, and concentrated to yield 0.92 gof product.

B. 14.15-dehydroerythromycin A 9-[O-(1-isopropoxycyclohexyl)]oxime

The oxime from (A) (0.92 g) was dissolved in 6.2 mL of CH₂Cl₂ andtreated with 1,1-diisopropoxycyclohexane (1.23 g) and pyridiniump-toluenesulfonate (0.464 gm) for 15 hours at ambient temperature. Themixture was diluted with 160 ML of CH₂Cl₂, then washed sequentially withsaturated NaHCO₃, water, and brine. The organic phase was dried withMgSO₄, filtered, and evaporated to yield a brown syrup. Chromatographyon silica gel (gradient from toluene to 1:1 toluene/acetone+1% Et₃N)yielded 0.998 g of product.

C. 2′,4″-bis(O-trimethylsilyl)-14,15-dehydroerythromycin A9-[O-(1-isopropoxycyclohexyl)]oxime

A solution of 14,15-dehydroerythromycin A9-[O-(1-isopropoxycyclohexyl)]oxime (998 mg, 9.96) in 11.25 mL of CH₂Cl₂was cooled on ice under inert atmosphere and treated with a solution ofchlorotrimethylsilane (0.24 mL) and 1-trimethylsilylimidazole (0.44 mL).After 30 minutes, the reaction was diluted with 250 mL of ethyl acetateand washed sequentially with saturated NaHCO₃, water, and brine. Theorganic phase was dried with MgSO₄, filtered, and evaporated to yield1.002 g of product.

D. 2′,4″-bis(O-trimethylsilyl)-6-O-methyl-14,15-dehydroerythromycin A9-[O-(1-isopropoxycyclohexyl)]oxime

A solution of 2′,4″-bis-O-trimethylsilyl-14,15-dehydroerythromycin A9-[O-(1-isopropoxycyclohexyl)]oxime (1.00 g, 20.7 mmol) in 9.69 mL of1:1 tetrahydrofuran/methylsulfoxide was cooled to 10° C. and treatedwith 0.97 mL of 2.0 M methyl bromide in ether under inert atmosphere. Amixture of methylsulfoxide (1.94 mL) and 1.0 M potassium tert-butoxidein tetrahydrofuran (1.94 mL) was added slowly. The reaction wasmonitored by thin-layer chromatography (silica gel, 10:1toluene/acetone), and was judged complete after addition of 1.6 molarequivalents of base. The reaction was diluted with 200 mL of ethylacetate and 70 mL of saturated NaHCO₃. The mixture was transferred to aseparatory funnel, diluted with 850 mL of ethyl acetate and 280 mL ofsaturated NaHCO₃, then washed sequentially with water and brine. Theorganic phase was dried with MgSO₄, filtered through Celite, andevaporated to yield 21.2 g of crude6-O-methyl-2′,4″-bis-O-trimethylsilyl-14,15-dehydroerythromycin A9-[O-(1-isopropoxycyclohexyl)]oxime. This was carried on without furtherpurification.

E. 6-O-methyl-14,15-dehydroerythromycin A 9-oxime

A solution of6-O-methyl-2′,4″-bis-O-trimethylsilyl-14,15-dehydroerythromycin A9-[O-(1-isopropoxycyclohexyl)]oxime (1.0 g) in 9.8 mL of 2:1acetonitrile/water was treated with 5.3 mL of acetic acid, and stirredfor 8 hours at ambient temperature. The mixture was concentrated envacuo, then repeatedly concentrated after addition of toluene to yield0.797 g of crude 6-O-methyl-14,15-dehydroerythromycin A 9-oxime.

F. 6-O-methyl-14,15-dehydroerythromycin A

A solution of 6-O-methyl-14,15-dehydroerythromycin A 9-oxime (0.797 g)and sodium hydrosulfite (85%, 1.02 g) in 7.5 mL of 1:1 ethanol/water wasplaced under inert atmosphere. Formic acid (0.186 mL) was addeddropwise, and the mixture was stirred at 80° C. for 3 hours. Aftercooling to ambient temperature, the reaction was adjusted to pH 10 with6 N NaOH and extracted three times with 150-mL portions of ethylacetate. The organic extracts were combined and washed sequentially withsaturated NaHCO₃, water, and brine. The organic phase was dried withMgSO₄, filtered, and evaporated to yield 0.68 g of6-O-methyl-14,15-dehydroerythromycin A suitable for further conversion.

Example 6 Synthesis of 6-O-methyl-15-methylerythromycin A, i.e. Formula(4) where R_(d)=propyl, R_(a)=Me, R_(c)=H, R_(e)=H

A. 15-Methylerythromycin A 9-Oxime:

A suspension of 15-methylerythromycin A (20.0 g, 85% purity, 22.6 mmol)in 40 mL of 2-propanol was treated with 20.5 mL of 50% aqueoushydroxylamine and stirred until dissolved. Acetic acid (6.41 mL) wasadded and the mixture was stirred for 15 hours at 50° C. Upon cooling toambient temperature, saturated NaHCO₃ was added and the mixture wasconcentrated en vacuo to remove isopropanol. The resulting aqueousmixture was extracted three times with 250-mL portions of CHCl₃. Theorganic extracts were combined, washed with saturated NaHCO₃, water, andbrine, then dried over MgSO₄, filtered, and concentrated to yield 20.5 gof crude product. Analysis by LC/MS revealed a 94:6 mixture of E and Zoximes, [M+H]⁺=764.

B. 15-Methylerythromycin A 9-[O-(1-isopropoxcyyclohexyl)]oxime:

The crude oxime from above (20.5 g) was dissolved in 55 mL of CH₂Cl₂ andtreated with 1,1-diisopropoxycyclohexane (27.3 mL) and pyridiniump-toluenesulfonate (9.8 gm) for 15 hours at ambient temperature. Themixture was diluted with 160 mL of CH₂Cl₂, then washed sequentially withsaturated NaHCO₃, water, and brine. The organic phase was dried withMgSO₄, filtered, and evaporated to yield a brown syrup. Chromatographyon silica gel (gradient from 2:1 to 3:2 hexanes/acetone +1% Et₃N)yielded 18.0 g of product.

C. 2′,4″-bis-O-trimethylsilyl-15-methylerythromycin A9-[O-(1-isopropoxycyclohexyl)]oxime:

A solution of 15-Methylerythromycin A9-[O-(1-isopropoxycyclohexyl)]oxime (9.00 g, 9.96 mmol) in 25 mL ofCH₂Cl₂ was cooled on ice under inert atmosphere and treated with asolution of chlorotrimethylsilane (1.89 mL) and1-trimethylsilylimidazole (3.65 mL) in 8 mL of CH₂Cl₂. After 30 minutes,the reaction was diluted with 250 mL of ethyl acetate and washedsequentially with saturated NaHCO₃, water, and brine. The organic phasewas dried with MgSO₄, filtered, and evaporated. The crude product waspurified by silica gel chromatography (gradient from hexanes to 10:1hexanes/acetone +1% Et₃N), yielding 7.8 g of product.

D. 6-O-Methyl-2′,4″-bis-O-trimethylsilyl-15-methylerythromycinA9-[O-(1-isopropoxycyclohexyl)]oxime:

A solution of 2′,4″-bis-O-trimethylsilyl-15-methylerythromycin A9-[O-(1-isopropoxycyclohexyl)]oxime (21.7 g, 20.7 mmol) in 41.4 mL oftetrahydrofuran was cooled to 10° C. and treated with 41.4 mL ofmethylsulfoxide and 20.7 mL of 2.0 M methyl bromide in ether under inertatmosphere. A mixture of methylsulfoxide (41.4 mL) and 1.0 M potassiumtert-butoxide in tetrahydrofuran (41.4 mL) was added at a rate of ca. 20mL per hour. The reaction was monitored by thin-layer chromatography(silica gel, 10:1 toluene/acetone), and was judged complete afteraddition of 1.6 molar equivalents of base. The reaction was diluted with200 mL of ethyl acetate and 70 mL of saturated NaHCO₃. The mixture wastransferred to a separatory funnel, diluted with 850 mL of ethyl acetateand 280 mL of saturated NaHCO₃, then washed sequentially with water andbrine. The organic phase was dried with MgSO₄, filtered through Celite,and evaporated to yield 21.2 g of crude6-O-methyl-2′,4″-bis-O-trimethylsilyl-15-methylerythromycin A9-[O-(1-isopropoxycyclohexyl)]oxime. This was carried on without furtherpurification.

E. 6-O-Methyl-15-methylerythromycin A 9-oxime:

A solution of6-O-methyl-2′,4″-bis-O-trimethylsilyl-15-methylerythromycin A9-[O-(1-isopropoxycyclohexyl)]oxime (21.2 g) in 110 mL of acetonitrilewas treated with 55 mL of water and 67 mL of acetic acid, and stirredfor 8 hours at ambient temperature. The mixture was concentrated envacuo, then repeatedly concentrated after addition of toluene to yield19.7 g of 6-O-methyl-15-methylerythromycin A 9-oxime.

F. 6-O-Methyl-15-methylerythromycin A:

A solution of 6-O-methyl-15-methylerythromycin A 9-oxime (19.7 g) andsodium hydrosulfite (85%, 23.1 g) in 280 mL of 1:1 ethanol/water wasplaced under inert atmosphere. Formic acid (3.75 mL) was added dropwise,and the mixture was stirred at 80° C. for 4.5 hours. After cooling toambient temperature, the reaction was treated with saturated NaHCO₃ andextracted three times with 400-mL portions of ethyl acetate. The organicextracts were combined and washed sequentially with saturated NaHCO₃,water, and brine. The organic phase was dried with MgSO₄, filtered, andevaporated to yield 15.1 g of 6-O-methyl-15-methylerythromycin Asuitable for further conversion.

Example 7 Synthesis of5-O-(2′-acetyldesosaminyl)-10,11-anhydro-3-deoxy-3-oxo-6-O-methyl-14-norerythronolideA (Anhydro form of Formula (6), R_(a)=Me, R_(d)=Me, R_(c)=Ac, R_(b)=H)

A. 5-O-Desosaminyl-6-O-methyl-14-norerythronolide A:

A mixture of 6-O-methyl-14-norerythromycin A (77 mg), 0.073 ml of 12 NHCl and water (2 ml) was stirred at ambient temperature for 3 hours. Themixture was brought to pH 8 with 8 N KOH, and extracted with ethylacetate. The organic extract was washed with brine, dried with MgSO₄,filtered, and evaporated. The residue was chromatographed on silica gel(3:1/hexanes:acetone, 1% triethylamine) to give pure product as a whitesolid (42 mg). Mass spectrometry reveals [M+H]⁺=576.

B. 5-O-(2′-Acetyldesosaminyl)-6-O-methyl-14-norerythronolide A:

A mixture of 5-O-desosaminyl-6-O-methyl-14-norerythronolide A (73 mg),potassium carbonate (20 mg), acetic anhydride (14 μl) and acetone (1 ml)was stirred at ambient temperature for 18 hours. Ethyl acetate wasadded, washed with water and brine, dried over MgSO₄, filtered, andevaporated. The residue was chromatographed on silica gel(3:1/hexanes:acetone, 1% triethylamine) to yield the pure product (71mg) as a white solid. Mass spectrometry reveals [M+H]⁺=618.

C.5-O-(2-Acetyldesosaminyl)-3-deoxy-3-oxo-6-O-methyl-14-norerythronolide A(Formula (1), R_(a)=OH, R_(d)=Me, R_(f)=Me, R_(b)=H R_(c)=Ac):

A solution of 5-O-(2′-acetyldesosaminyl)-6-O-methyl-14-norerythronolideA (99 mg) and 1-(3-dimethylaminopropyl)-3-ethylcarbodiidmide (EDC)hydrochloride (206 mg) in dichloromethane (2 ml) was treated with DMSO(0.21 ml) and cooled to 5° C. A solution of pyridinium trifluoroacetate(208 mg) in dichloromethane (2 ml) was added via a syringe pump in 4hours. Ethyl acetate was then added, washed with saturated NaHCO₃,water, brine, and dried over MgSO₄, filtered, and evaporated. Theresidue was chromatographed on silica gel (3:1/hexanes:acetone, 1%triethylamine) to yield the pure product (94 mg) as a white solid. Massspectrometry reveals [M+H]⁺=616.

D.5-O-(2′-Acetyldesosaminyl)-3-deoxy-3-oxo-11-O-methanesulfonyl-6-O-methyl-14-norerythronolideA:

To a solution of5-O-(2′-acetyldesosaminyl)-3-deoxy-3-oxo-6-O-methyl-14-norerythronolideA (93 mg) in dry pyridine (1 ml) was added methanesulfonyl chloride(0.057 ml) at 5° C. After 3 hours at 5° C., the reaction was warmed toambient temperature and kept for an additional 15 hours. The mixture wasdiluted with ethyl acetate, washed with saturated NaHCO₃(2×), water(3×), brine, and dried over MgSO₄, filtered, and evaporated. The residuewas chromatographed on silica gel (2:1 /hexanes:acetone, 1%triethylamine) to yield the pure product (72 mg) as a white solid. Massspectrometry reveals [M+H]⁺=695.

E.5-O-(2′-Acetyldesosaminyl)-10,11-anhydro-3-deoxy-3-oxo-6-O-methyl-14-norerythronolideA:

A solution of5-O-(2′-acetyldesosaminyl)-3-deoxy-3-oxo-11-O-methanesulfonyl-6-O-methyl-14-norerythronolideA (73 mg) in acetone (1 ml) was treated with diazabicycloundecene (32μl) at ambient temperature for 18 hours. The mixture was diluted withethyl acetate, washed with saturated NaHCO₃, water, brine, and driedover MgSO₄, filtered, and evaporated. The residue was chromatographed onsilica gel (2:1/hexanes: acetone, 1% triethylamine) to yield the pureproduct (50 mg) as a white solid. Mass spectrometry reveals [M+H]⁺=598.¹³C-NMR (CDCl₃, 100 MHz): δ 207.02, 204.50, 169.63, 168.72, 142.52,139.40, 101.87, 80.61, 80.02, 77.14, 72.66, 71.48, 69.09, 63.56, 51.35,50.56, 47.12, 40.61, 39.73, 37.36, 30.36, 21.32, 21.06, 20.96, 20.67,18.45, 14.34, 13.89, 13.55, 13.45.

Example 8 Synthesis of2′-O-Benzoyl-6-O-methyl-3-descladinosyl-3-oxo-10,11-anhydro-14,15-dehydroerythromycinA (Anhydro form of Formula (6), R_(d)=—CH═CH₂, R_(a)=Me, R_(b)=H,R_(c)=Benzoyl)

A. 2′-O-Benzoyl-6-O-methyl-14,15-dehydroerythromycin A

A solution of 6-O-methyl-14,15-dehydroerythromycin A (668 mg), benzoicanhydride (385 mg), and triethylamine (0.25 mL) in 3.6 mL of CH₂Cl₂ wasstirred for 2 days. After addition of saturated NaHCO₃, the mixture wasextracted three times with CH₂Cl₂. The organic extracts were combinedand evaporated to dryness, and the product 2.5 was purified by silicachromatography (90:9:1 toluene/acetone/Et₃N) to give 477 mg of product;LC-MS shows [M+H]⁺=850.6.

B. 2′-O-Benzoyl-6-O-methyl-4″,11-bis(O-methanesulfonyl)-14,15-dehydroerythromycin A

A solution of 2′-O-benzoyl-6-O-methyl-14,15-dehydroerythromycin A (549mg) and methanesulfonyl chloride (0.50 mL) in 2.39 mL of pyridine wasstirred for 24 hours, then diluted with CH₂Cl₂ and saturated NaHCO₃. Themixture was extracted three times with CH₂Cl₂. The organic extracts werecombined and evaporated to dryness, and the product was purified bysilica chromatography (90:9:1 toluene/acetone/Et₃N) to give 530 mg ofproduct; LC-MS shows [M+H]⁺=1006.5.

C.2′-O-Benzoyl-6-O-methyl-4″-O-methanesulfonyl-10,11-anhydro-14,15-dehydroerythromycinA

A mixture of2′-O-benzoyl-6-O-methyl-4″,11-bis(O-methanesulfonyl)14,15-dehydroerythromycinA (59 mg) and diazabicycloundecene (0.018 mL) in 0.195 mL of acetone wasstirred for 24 hours, then dried in vacuo. The product was purified bysilica chromatography (90:9:1 toluene/acetone/Et₃N) to give 50 mg ofproduct; LC-MS shows [M+H]⁺=910.5.

D.2′-O-Benzoyl-6-O-methyl-3-descladinosyl-10,11-anhydro-14,15-dehydroerythromycinA

A mixture of2′-O-benzoyl-6-O-methyl-4″-O-methanesulfonyl-10,11-anhydro-14,15-dehydroerythromycinA (337 mg), 1.5 mL of acetonitrile, and 6.9 mL of 3 N HCl was stirredfor 22 hours. The acetonitrile was removed in vacuo, the pH of theaqueous residue was adjusted to 12 by addition of NaOH, and the productwas extracted using 4 portions of CH₂Cl₂. The combined extracts weredried and evaporated. The product was purified by silica chromatography(gradient from 96:4 CH₂Cl₂/MeOH to 95:4:1 CH₂Cl₂/MeOH/Et₃N) to give 197mg, [M+H]⁺=674.4.

E.2′-O-Benzoyl-6-O-methyl-3-descladinosyl-3-oxo-10,11-anhydro-14,15-dehydroerythromycinA

A suspension of2′-O-benzoyl-6-O-methyl-3-descladinosyl-10,11-anhydro-14,15-dehydroerythromycinA (226 mg) and the Dess-Martin periodinane (427 mg) in 14.6 mL of CH₂Cl₂(14.6 mL) was stirred for 1 hour. The mixture was diluted with CH₂Cl₂and saturated NaHCO₃. The product was extracted using 3 portions ofCH₂Cl₂, and the extracts were combined, dried, and evaporated. Silicagel chromatography (90:9:1 toluene/acetone/Et₃N) yielded the product,168 mg. [M+H]⁺=672.4. ¹³C-NMR (CDCl₃, 100 MHz): δ 206.78, 203 (br),168.19, 165.08, 141.36, 139.58, 132.74, 131.51, 130.46, 129.79, 128.25,120.18, 102.09, 80.79, 80.40, 78.70, 72.52, 71.91, 69.19, 63.76, 51.10,50.54, 47.08, 40.73, 39.87, 37.77, 31.23, 22.13, 20.98, 18.52, 14.28,14,15, 13.55.

Example 9 Synthesis of5-O-(2′-acetyldesosaminyl)-10,11-anhydro-3-deoxy-3-oxo-6-O-methyl-15-methylerythronolideA (Anhydro form of Formula (6); R_(a)=Me, R_(d)=propyl, R_(b)=H,R_(c)=Ac)

A. 6-O-methyl-3-descladinosyl-15-methylerythromycin A

A mixture of 6-O-methyl-15-methylerythromycin A (15.1 g) and 280 mL of0.5 N HCl was stirred at ambient temperature for 3 hours. The pH wasadjusted to 9 by addition of 6 N NaOH and the resulting precipitate wascollected by vacuum filtration, washed with water, and dried. Thefiltrate was extracted three times with 400-mL portions of ethylacetate. The organic extracts were combined, washed sequentially withsaturated NaHCO₃, water, and brine, then dried over MgSO₄, filtered, andevaporated to provide further product. The combined crude products werechromatographed on silica gel to yield 9.35 g of pure6-O-methyl-3-descladinosyl-15-methylerythromycin A. ES-LC/MS shows[M+H]⁺=605.

B. 2′-O-Acetyl-6-O-methyl-3-descladinosyl-15-methylerythromycin A

A solution of acetic anhydride (2.92 mL) in 35 mL of ethyl acetate wasadded dropwise to a solution of6-O-methyl-3-descladinosyl-15-methylerythromycin A (9.35 g) in 40 mL ofethyl acetate. The mixture was stirred for 30 minutes after completionof addition, then concentrated. Chromatography on silica gel (2:1hexanes/acetone) gave 8.35 g of2′-O-acetyl-6-O-methyl-3-descladinosyl-15-methylerythromycin A. ES-LC/MSshows [M+H]⁺=647.

C. 2′-O-Acetyl-6-O-methyl-3-descladinosyl-3-oxo-15-methylerythromycin A

A solution of2′-O-acetyl-6-O-methyl-3-descladinosyl-15-methylerythromycin A (8.3 g)and 1-ethyl-3-(dimethylaminopropyl)carbodiimide hydrochloride (16.51 g)in 64 mL of dichloromethane and 15.47 mL of methylsulfoxide was placedunder inert atmosphere and cooled on ice. A solution of pyridiniumtrifluoroacetate (16.63 g) in 64 mL of dichloromethane was added at arate such that addition would be complete in 4 hours, and the reactionwas monitored by thin-layer chromatography. Complete reaction wasobserved after addition of 73% of the solution and so the reaction wasthen quenched by addition of 600 mL of ethyl acetate and 200 mL ofsaturated NaHCO₃. The organic layer was collected and washedsequentially with saturated NaHCO₃, water, and brine, then dried overMgSO₄, filtered, and evaporated to yield 8.4 g of crude product.Chromatography on silica gel (3:1 hexanes/acetone) gave 6.75 g of2′-O-acetyl-6-O-methyl-3-descladinosyl-3-oxo-15-methylerythromycin A.ES-LC/MS shows [M+H]⁺=645.

D.2′-O-Acetyl-6-O-methyl-3-descladinosyl-3-oxo-11-O-methanesulfonyl-15-methylerythromycinA

Methanesulfonylchloride (5.68 mL) was added dropwise to a solution of2′-O-acetyl-6-O-methyl-3-descladinosyl-3-oxo-15-methylerythromycin A(6.73 g) in 35 mL of pyridine at 0° C. The mixture was brought toambient temperature and quenched by addition of 700 mL of ethyl acetateand 200 mL of saturated NaHCO₃. The organic layer was collected andwashed sequentially with saturated NaHCO₃, water, and brine, then driedover MgSO₄, filtered, and evaporated to yield 8.2 g of crude product.Chromatography on silica gel (5:2 hexanes/acetone) gave 5.04 g of2′-O-acetyl-6-O-methyl-3-descladinosyl-3-oxo-11-O-methanesulfonyl-15-methylerythromycinA. ES-LC/MS shows [M+H]⁺=723.

E.2′-O-Acetyl-6-O-methyl-3-descladinosyl-3-oxo-10,11-anhydro-15-methylerythromycinA

1,8-Diazabicyclo[5.4.0]undec-7-ene (5.22 mL) was added dropwise to asolution of 2′-O-acetyl-6-O-methyl-3-descladinosyl-3-oxo-11-O-methanesulfonyl-15-methylerythromycin A (5.03 g) in 23 mL ofacetone. The solution was concentrated after 4.5 hours, and the residuewas chromatographed on silica gel (5:2 hexanes/acetone) to give 3.72 gof2′-O-acetyl-6-O-methyl-3-descladinosyl-3-oxo-10,11-anhydro-15-methylerythromycinA. ES-LC/MS shows [M+H]⁺=627.

Example 10 Synthesis of5-O-(2′-acetyldesosaminyl)-10,11-anhydro-3,6-dideoxy-3-oxo-15-methylerythronolideA (Formula (6), anhydro form, R_(d)=propyl, OR_(a) replaced by H,R_(b)=H, R_(c)=Ac)

To a solution of 6-deoxy-15-methyl erythromycin C (220mg, 0.307mmol) indichloromethane (5 mL) were given potassium carbonate (50 mg) and aceticanhydride (100 L, 0.9 mmol), and the reaction was stirred at roomtemperature for 16 hours. The solution was filtered, sodium hydroxide(1N, 25 mL) and brine (25 mL) added and the aqueous layer was extractedwith ethyl acetate 6 times. The combined organic layers were dried withsodium sulfate, filtered, and the solvent removed in vacuo. The crudeproduct the 2′ acetylated form of the starting material was carried onto the next step.

The crude product was dissolved in pyridine (5 mL) and mesyl chloride(70L, 0.9mmol) was added. The reaction was stirred at −20° C. for 2days, poured on sodium hydroxide (1N, 25 mL) and brine (25 mL) and theaqueous layer was extracted with ethyl acetate 6 times. The combinedorganic layers were dried with sodium sulfate, filtered, and the solventremoved in vacuo. The residue was purified by chromatography on silicagel (toluene/acetone=3:1, 1% ammonium hydroxide) to yield 11,4″dimesylated form (190 mg, 68% over two steps).

The 11,4″ dimesylated form (190 mg, 0.21 mmol) was dissolved in acetone(7 mL) and DBU (63L, 0.42 mmol) was added, and the reaction was stirredat room temperature over night. The mixture was poured on sodiumhydroxide (1N, 25 mL) and brine (25 mL) and the aqueous layer wasextracted with ethyl acetate 6 times. The combined organic layers weredried with sodium sulfate, filtered, and the solvent removed in vacuo.The crude product, the 10,11-dehydro form of 6-deoxy-15-methylerythromycin was carried on to the next step.

To the crude product from the above step was added hydrochloric acid (30mL, 3N) and ethanol (2 mL) and the mixture was stirred vigorously for 6hours. Sodium hydroxide (5 mL, 10N) was added and the aqueous layer wasextracted with ethyl acetate 6 times. The combined organic layers weredried with sodium sulfate, filtered, and the solvent removed in vacuo.The crude product, the anhydro form of formula (6) (but with OH atposition 3) where R_(d)=propyl, OR_(a) is replaced by H, R_(b)=R_(c)=H,was carried on to the next step.

To the crude product from the above step in dichloromethane (5 mL) wasadded acetic anhydride (50L, 0.45 mmol) and potassium carbonate (100 mg)and the mixture was stirred vigorously for 9 hours. The reaction wasfiltered, sodium hydroxide (20 mL, 1N) and brine (25 mL) were added andthe aqueous layer was extracted with ethyl acetate 6 times. The combinedorganic layers were dried with sodium sulfate, filtered, and the solventremoved in vacuo. The residue was purified by chromatography on silicagel (toluene/acetone=3:1, 1% ammonium hydroxide) to yield the 2′acetylated form of the starting material (110 mg, 89% over three steps).

The product of the above step (110 mg, 0.184 mmol) was dissolved indichloromethane (10 mL) and Dess-Martin reagent (220 mg, 0.53 mmol) wasadded. The reaction was stirred at room temperature for 45 min. Thereaction was quenched with Sodium hydroxide (20 mL, 1N) and brine (25mL) and the aqueous layer was extracted with ethyl acetate 6 times. Thecombined organic layers were dried with sodium sulfate, filtered, andthe solvent removed in vacuo. The residue was purified by chromatographyon silica gel (toluene/acetone, gradient=6:1-3:1, 1% ammonium hydroxide)to yield the compound of formula (6), anhydro form, where R_(d)=propyl,OR_(a) is replaced by H, R_(b)=H, R_(c)=Ac (94 mg, 86%).

Example 11 I. Compound of Formula Formula (4): R_(d)=propyl, R_(a)=allyl

Step 1. Allylation of Intermediate Antibiotic at 6-OH:

A solution of 2′,4″-bis-O-trimethylsilyl-15-methylerythromycin A9-[O-(1-isopropoxycyclohexyl)]oxime (formula (I) (R_(a) is OH, R_(d) ispropyl, protected at 2′ and 4″ with trimethylsilyl and at C9=O by theisoproxycyclohexyl oxime)) (7.8 g, 7.44 mmol) in 30 mL oftetrahydrofuran was cooled on ice and treated with 30 mL ofmethylsulfoxide and 2.58 mL of freshly distilled allyl bromide underinert atmosphere. A mixture of methylsulfoxide (29.8 mL) and 1.0 Mpotassium tert-butoxide in tetrahydrofuran (29.8 mL) was added at a rateof 1.33 molar equivalents of base per hour. The reaction was monitoredby thin-layer chromatography (silica gel, 10:1 toluene/acetone), and wasjudged complete after addition of 3.6 molar equivalents of base. Thereaction was diluted with 700 mL of ethyl acetate and washedsequentially with saturated NaHCO₃, water, and brine. The organic phasewas dried with MgSO₄, filtered, and evaporated to yield 8.08 g of crude6-O-allyl-2′,4″-bis-O-trimethylsilyl-15-methylerythromycin A9-[O-(1-isopropoxycyclohexyl)]oxime. This was carried on without furtherpurification.

Step 2: A solution of6-O-allyl-2′,4″-bis-O-trimethylsilyl-15-methylerythromycin A9-[O-(1-isopropoxycyclohexyl)]oxime (8.08 g) in 42 mL of acetonitrilewas treated with 21 mL of water and 24 mL of acetic acid, and stirredfor 18 hours at ambient temperature. The mixture was concentrated afteraddition of 2-propanol, then repeatedly after addition of toluene toyield 7.7 g of crude product. Chromatography on silica gel (gradientfrom 2:1 to 1:1 hexanes/acetone +1% Et₃N) gave 3.75 g of6-O-allyl-15-methylerythromycin A 9-oxime.

Step 3: A solution of 6-O-allyl-15-methylerythromycin A 9-oxime (3.75 g)and sodium hydrosulfite (85%, 5.37 g) in 66 mL of 1:1 ethanol/water wasplaced under inert atmosphere. Formic acid (0.845 mL) was addeddropwise, and the mixture was stirred at 80° C. for 3.5 hours. Aftercooling to ambient temperature, the reaction was adjusted to pH 10 with6 N NaOH and extracted three times with 150-mL portions of ethylacetate. The organic extracts were combined and washed sequentially withsaturated NaHCO₃, water, and brine. The organic phase was dried withMgSO₄, filtered, and evaporated to yield 3.42 g of6-O-allyl-15-methylerythromycin A suitable for further conversion.

II. Compound of Formula (4): R_(d)=Me, R_(a)=allyl

Step 1: Allylation of Intermediate Antibiotic at 6-OH:

A solution of 2′,4″-bis-O-trimethylsilyl-14-norerythromycin A9-[O-(1-isopropoxycyclohexyl)]oxime, Formula (I), (R_(a) is OH, R_(d) ismethyl, protected at 2′ and 4″ with trimethylsilyl and at C9=O by theisoproxycyclohexyl oxime) (202 mg) in tetrahydrofuran (0.4 mL), DMSO(0.4 mL), and ether (0.04 mL) was cooled to 10° C. and treated with0.035 mL of freshly distilled allyl bromide under inert atmosphere. Amixture of methylsulfoxide (0.4 mL) and 1.0 M potassium tert-butoxide intetrahydrofuran (0.4 mL) was added at a rate 0.22 mL/hour. The reactionwas monitored by thin-layer chromatography (silica gel, 5:1toluene/acetone. The reaction was diluted with ethyl acetate and washedsequentially with saturated NaHCO₃, water, and brine. The organic phasewas dried with MgSO₄, filtered, and evaporated to yield 222 mg of crude6-O-allyl-2′,4″-bis-O-trimethylsilyl-14-norerythromycin A9-[O-(1-isopropoxycyclohexyl)]oxime. This was carried on without furtherpurification.

Step 2: A solution of6-O-allyl-2′,4″-bis-O-trimethylsilyl-14-norerythromycin A9-[O-(1-isopropoxycyclohexyl)]oxime (222 mg) in 4 mL of acetonitrile wastreated with 2 mL of water and 2.4 mL of acetic acid, and stirred for 18hours at ambient temperature. The mixture was concentrated afteraddition of 2-propanol, then repeatedly after addition of toluene toyield 220 mg of crude 6-O-allyl-14-norerythromycin A 9-oxime.

Step 3: A solution of 6-O-allyl-14-norerythromycin A 9-oxime (220 mg)and sodium hydrosulfite (85%, 322 mg) in 4 mL of 1:1 ethanol/water wasplaced under inert atmosphere. Formic acid (0.050 mL) was addeddropwise, and the mixture was stirred at 80° C. for 15 hours. Aftercooling to ambient temperature, the reaction was adjusted to pH 10 with6 N NaOH and extracted three times with 150-mL portions of ethylacetate. The organic extracts were combined and washed sequentially withsaturated NaHCO₃, water, and brine. The organic phase was dried withMgSO₄, filtered, and evaporated to yield 156 mg of6-O-allyl-14-norerythromycin A suitable for further conversion.

Other embodiments: In a similar manner, compounds of formula (4) whereinY and Z are, together, =O, R_(a) is allyl, is prepared from anintermediate where R_(d) is butyl, benzyl, vinyl, or 3-hydroxybutyl.

Example 12 Conversion to Formula (4) to Formula (6)

Step 1. A mixture of the compound prepared in Example 11, II (77 mg,crude), 0.073 ml of 12 N HCl and water (2 ml) was stirred at ambienttemperature for 3 hours. The mixture was brought to pH 8 with 8 N KOH,and extracted with ethyl acetate. The organic extract was washed withbrine, dried with MgSO₄, filtered, and evaporated. The residue waschromatographed on silica gel (3:1/hexanes:acetone, 1% triethylamine) togive pure product as a white solid (42 mg).

Step 2. To protect the 2′ OH, a mixture the above compound (73 mg),potassium carbonate (20 mg), acetic anhydride (14 μl) and acetone (1 ml)was stirred at ambient temperature for 18 hours. Ethyl acetate wasadded, washed with water and brine, dried over MgSO₄, filtered, andevaporated. The residue was chromatographed on silica gel(3:1/hexanes:acetone, 1% triethylamine) to yield the pure product (71mg) as a white solid.

Step 3. A solution of the compound resulting from step 2 (99 mg) and1-(3-dimethylaminopropyl)-3-ethylcarbodiidmide (EDC) hydrochloride (206mg) in dichloromethane (2 ml) was treated with DMSO (0.21 ml) and cooledto 5° C. A solution of pyridinium trifluoroacetate (208 mg) indichloromethane (2 ml) was added via a syringe pump in 4 hours. Ethylacetate was then added, washed with saturated NaHCO₃, water, brine, anddried over MgSO₄, filtered, and evaporated. The residue waschromatographed on silica gel (3:1/hexanes:acetone, 1% triethylamine) toyield the pure compound of formula (6) (94 mg, R_(a) is allyl, R_(c) isacetate and R_(d) is CH₃).

Step 4. To deprotect 2′ OH, a solution of the compound resulting fromstep 3 (94 mg) in 5 mL methanol was stirred at room temperature for 24hours. The solvent was removed in vacuo to give the desired compound offormula (6) (R_(a) is allyl, R_(c) is H, and R_(d) is CH₃).

Other embodiments: In a similar manner, compounds of formula (4) whereinR_(a) is allyl, R_(c) is H, and R_(d) is propyl, butyl, benzyl, vinyl,or 3-hydroxybutyl is prepared.

Example 13 Preparation of Compounds of Formula (5)

The compound of formula (4), prepared as the 6-allyl derivative inExample 11, is protected at the 2′ position, treated with acid anddehydrated, then deprotected to obtain the compound of formula (5), asshown in FIG. 1, wherein R_(c) is H, and R_(a) is allyl. Similarly,compounds of formula (6) wherein R_(d) is propyl, butyl, benzyl, vinyl,or 3-hydroxybutyl, are prepared as described above using as startingmaterial the compounds of formula (I) wherein R_(d) is as set forthabove.

Example 14 Conversion of ═O at Position 9 to ═NOH

According to the procedure of Example 6A, the carbonyl at position 9 oferythromycins are converted to the corresponding oximes.

Example 15 Conversions at —OR_(a)

A. Ally→Propyl

A solution of any of the compounds prepared above (0.2 mmol) in ethanolis flushed with nitrogen and 10% palladium on carbon (20 mg) added. Themixture is then flushed with hydrogen and the reaction mixture stirredovernight under positive hydrogen pressure. The reaction mixture isfiltered and concentrated in vacuo to give a glass. Chromatography onsilica gel (95:5:0.5 dichloromethane-methanol-ammonia) gives the propylcompounds as white solids.

B. Allyl→—CH₂CHO

Ozone is passed through a −78° C. solution in dichloromethane (100 mL)of any of the compounds resulting above (4.0 mmol) for 45 minutes. Thereaction mixture is then flushed with nitrogen for 10 minutes. Dimethylsulfide (1.46 mL, 20 mmol) is added at −78° C. and the reaction mixturestirred for 30 minutes at 0° C. The reaction mixture is concentrated invacuo to give a white foam which is used without further purification byheating a solution of the compound in THF (40 mL, 4.0 mmol) andtriphenylphosphine (2.62 g, 10.0 mmol) at 55° C. for 2.5 hours. Thereaction mixture is concentrated in vacuo to give a white foam.Chromatography on silica gel (1:1 acetone-hexane, then 75:25:0.5acetone-hexane-triethylamine) gives the desired compound as a whitesolid.

C. Allyl→—CH₂CH═NOH

To a solution in methanol (5 mL) of the compound prepared in B whereinR_(a) is —CH₂CHO, (0.08 mmol) is added triethylamine (31 μL, 0.225 mmol)and hydroxylamine hydrochloride (7.7 mg, 0.112 mmol) and the reactionmixture stirred for 6 hours at ambient temperature. The reaction mixtureis taken up in ethyl acetate and washed with aqueous 5% sodiumbicarbonate and brine, dried over sodium sulfate, and concentrated invacuo to give a clear glass. Chromatography on silica gel (95:5:0.5dichloromethane-methanol-ammonia) gives the compound as a white solid.

D. —CH₂CH═NOH→—CH₂CN

To a solution under nitrogen of the compound prepared in C (0.267 mmol)in THF (5 mL) is added diisopropylcarbodiimide (83 μL, 0.534 mmol) andCuCl (2.7 mg, 0.027 mmol) and the reaction mixture is stirred overnightat ambient temperature. The reaction mixture is taken up in ethylacetate and washed with aqueous 5% sodium bicarbonate and brine, driedover sodium sulfate, and concentrated in vacuo to give a clear glass.Chromatography on silica gel (95:5:0.5 dichloromethane-methanol-ammonia)gives the desired compound as a white solid.

E. —CH₂CHO→—CH₂CH₂NH₂

To a solution in methanol (10 mL) of the compound prepared in B (0.276mmol) is added ammonium acetate (212 mg, 2.76 mmol) and the mixture iscooled to 0° C. Sodium cyanoborohydride (34 mg, 0.553 mmol) is added andthe reaction mixture stirred for 30 hours at 0° C. The reaction mixtureis taken up in ethyl acetate and washed with aqueous 5% sodiumcarbonate, aqueous 2% tris(hydroxymethyl)aminomethane, and brine, driedover sodium sulfate, filtered, and concentrated in vacuo. Chromatographyon silica gel (90:10:0.5 dichloromethane-methanol-ammonia) gives thedesired compound as a white solid.

F. —CH₂CHO→—CH₂CH₂NHCH₂-Phenyl

To a 0° C. solution in methanol (10 mL) of the compound prepared in B(0.200 mmol) is added acetic acid (114 μL, 2.00 mmol) and benzylamine(218 μL, 2.00 mmol) and the mixture is stirred for 10 minutes. Sodiumcyanoborohydride (24.8 mg, 0.400 mmol) is added and the reaction mixturestirred for 16 hours. Additional sodium cyanoborohydride (24.8 mg, 0.400mmol) is then added and stirring continued for 5 hours. The reactionmixture is taken up in ethyl acetate and washed with aqueous 5% sodiumcarbonate, aqueous 2% tris(hydroxymethyl)aminomethane, and brine, driedover sodium sulfate, filtered, and concentrated in vacuo. Chromatographyon silica gel (95:5:0.5 dichloromethane-methanol-ammonia) followed by asecond chromatography (50:50:0.5 acetone-hexanes-triethylamine) givesthe desired compound as a white foam.

G. —CH₂CHO→—CH₂CH₂NHCH₂CH₂-Phenyl

To a 0° C. solution in methanol (10 mL) of the compound prepared in B(0.200 mmol) is added acetic acid (114 μL, 2.00 mmol) and phenethylamine(218 μL, 2.00 mmol) and the mixture stirred for 10 minutes. Sodiumcyanoborohydride (24.8 mg, 0.400 mmol) is added and the reaction mixturestirred for 16 hours. The reaction mixture is taken up in ethyl acetateand washed with aqueous 5% sodium carbonate, aqueous 2%tris(hydroxymethyl)aminomethane, and brine, dried over sodium sulfate,filtered, and concentrated in vacuo. Chromatography on silica gel(90:10:0.5 dichloromethane-methanol-ammonia) gives the desired compound.

H. —CH₂CHO→—CH₂CH₂NHCH(CO₂CH₃)CH₂-Phenyl

To a 0° C. solution in methanol (10 mL) of the compound prepared in B(0.200 mmol) is added L-phenylalanine methyl ester hydrochloride (129mg, 0.600 mmol) and the mixture stirred for 10 minutes. Sodiumcyanoborohydride 924.8 mg, 0.400 mmol) is added and the reaction mixturestirred for 22 hours. The reaction mixture is taken up in ethyl acetateand washed with aqueous 5% sodium carbonate, aqueous 2%tris(hydroxymethyl)aminomethane, and brine, dried over sodium sulfate,filtered, and concentrated in vacuo. Chromatography on silica gel(95:5:0.5 dichloromethane-methanol-ammonia) gives the desired compound.

I. —CH₂CHO→—CH₂CH₂NHCH₂-(4-pridyl)

The desired compound is prepared according to the method in G, exceptsubstituting 4-aminomethylpyridine for phenethylamine.

J. —CH₂CH₂NH₂→—CH₂CH₂NHCH₂-(4-quinolyl)

To a solution of the compound prepared in E (0.15 mmol) in methanol (2mL) is added 4-quinolinecarboxaldehyde (23 mg, 0.15 mmol), acetic acid(8.6 μL, 0.15 mmol), and sodium cyanoborohydride (9.4 mg, 0.15 mmol) andthe reaction mixture is stirred for 15 hours. The reaction mixture istaken up in ethyl acetate and washed with aqueous 5% sodium carbonate,aqueous 2% tris(hydroxymethyl)aminomethane, and brine, dried over sodiumsulfate, filtered, and concentrated in vacuo. Chromatography on silicagel (95:10:0.5 dichloromethane-methanol-ammonia) gives the desiredcompound.

K. Allyl→—CH₂CH═CH-Phenyl

To a solution under nitrogen of the 2′ protected compound prepared inExample 10 (1.00 mmol), palladium(II)acetate (22 mg, 0.100 mmol), andtriphenylphosphine (52 mg, 0.200 mmol) in acetonitrile (5 mL) was addediodobenzene (220 μL, 2.00 mmol) and triethylamine (280 μL, 2.00 mmol)and the mixture is cooled to −78° C., degassed, and sealed. The reactionmixture is then warmed to 60° C. for 0.5 hours and stirred at 80° C. for12 hours, taken up in ethyl acetate and washed twice with aqueous 5%sodium bicarbonate, once with aqueous 2%tris(hydroxymethyl)aminomethane, and once with brine, dried over sodiumsulfate, filtered, and concentrated in vacuo. Chromatography on silicagel (95:5:0.5 dichloromethane-methanol-ammonia) gives the desiredcompound.

Deprotection is accomplished by heating in methanol.

Other embodiments of formulas (4)-(6) where R_(b) is H, R_(c) is H, andR_(d) is propyl, butyl, benzyl, vinyl, or 3-hydroxybutyl are thosewherein R_(a) is:

—CH₂CH₂CH₂-phenyl; —CH₂CH═CH-(4-methoxyphenyl); —CH₂CH═CH-(4-—CH₂CH═CH-(3-quinolyl); chlorophenyl); —CH₂CH₂CH₂OH; —CH₂C(O)OH;—CH₂CH₂NHCH₃; —CH₂CH₂NHCH₂OH; —CH₂CH₂N(CH₃)₂; —CH₂CH₂(1-morpholinyl);—CH₂C(O)NH₂; —CH₂NHC(O)NH₂; —CH₂NHC(O)CH₃; —CH₂F; —CH₂CH₂OCH₃; —CH₂CH₃;—CH₂CH═CH(CH₃)₂; —CH₂CH₂CH(CH₃)CH₃; —CH₂CH₂OCH₂CH₂OCH₃; —CH₂SCH₃;-cyclopropyl; —CH₂OCH₃; —CH₂CH₂F; —CH-cyclopropyl; —CH₂CH₂CHO;—C(O)CH₂CH₂CH₃; —CH₂-(4-nitrophenyl); —CH₂-(4-chlorophenyl);—CH₂-(4-methoxyphenyl); —CH₂-(4-cyanophenyl); —CH₂CH═CHC(O)OCH₃;—CH₂CH═CHC(O)OCH₂CH₃; —CH₂CH═CHCH₃; —CH₂CH═CHCH₂CH₃; —CH₂CH═CHCH₂CH₂CH₃;—CH₂CH═CHSO₂-phenyl; —CH₂C≡CSi(CH₃)₃ —CH₂C≡CCH₂CH₂CH₂CH₂CH₂CH₃;—CH₂C≡CCH₃; —CH₂-(2-pyridyl); —CH₂-(3-pyridyl); —CH₂-(4-pyridyl);—CH₂-(4-quinolyl); —CH₂NO₂; —CH₂C(O)OCH₃; —CH₂C(O)-phenyl;—CH₂C(O)CH₂CH₃; —CH₂Cl; —CH₂S(O)₂-phenyl; —CH₂CH═CHBr;—CH₂CH═CH-(4-quinolyl); —CH₂CH₂CH₂-(4-quinolyl); —CH₂CH═CH-(5-quinolyl);—CH₂CH₂CH₂-(5-quinolyl); —CH₂CH═CH-(4- —CH₂CH═CH-(7-benzimidazolyl).benzoxazolyl); or

Any of the foregoing compounds can be converted to the correspondingderivatives wherein Y and Z are together ═NOH in the manner described inExample 14 above.

Example 16 Preparation of Compound of Formula (1): L is CO, T is O,R_(a)═—CH₂CH═CH₂, R_(c) is H

Step 1. Protection at 2′-OH to Form Intermediate Compound of Compound(6) Having Hydroxyl Group at C-3, R_(a) is Allyl and R_(c) is Benzoyl.

To a solution of the product of Example 12 or other embodiment thereofwherein R_(d) is propyl, butyl, benzyl, vinyl or 3-hydroxybutyl (2.49 g,4.05 mmol) in dichloromethane (20 mL) is added benzoic anhydride (98%,1.46 g, 6.48 mmol) and triethylamine (0.90 mL, 6.48 mmol) and the whitesuspension is stirred for 26 hours at ambient temperature. Aqueous 5%sodium carbonate is added and the mixture is stirred for 20 minutes. Themixture is extracted with dichloromethane. The organic phase is washedwith aqueous 5% sodium bicarbonate and brine, dried over sodium sulfateand concentrated in vacuo to give a white foam. Chromatography on silicagel (30% acetone-hexanes) gives the protected compound.

Step 2. Oxidation to Form Compound (6), R_(a) is allyl, R_(c) isBenzoyl.

To a −10° C. solution under N₂ of N-chlorosuccinimide (0.68 g, 5.07mmol) in dichloromethane (20 mL) is added dimethylsulfide (0.43 mL, 5.92mmol) over 5 minutes. The resulting white slurry is stirred for 20minutes at −10° C. and then a solution of the compound resulting fromstep 1 (2.43 g, 3.38 mmol) in dichloromethane (20 mL) is added and thereaction mixture is stirred for 30 minutes at −10 to −5° C.Triethylamine (0.47 mL, 3.38 mmol) is added dropwise over 5 minutes andthe reaction mixture is stirred for 30 minutes at 0° C. The reactionmixture is extracted with dichloromethane. The organic phase is washedtwice with aqueous 5% sodium bicarbonate and once with brine, dried oversodium sulfate, and concentrated in vacuo to give a white foam.Chromatography on silica gel (30% acetone-hexanes) gives the oxidizedcompound.

Step 3: Form Cyclic Carbonate of Compound of Formula (1) fromIllustrative Scheme 5: R_(a) is —CH₂CH═CH₂, R_(c) is Benzoyl.

To a −35° C. solution under nitrogen in THF (60 mL) of the compoundprepared in step 2 (3.58 g, 5.00 mmol) is added sodiumhexamethyldisilazide (1.0 M in THF, 5.5 mL, 5.5 mmol) and the resultingwhite suspension is stirred for 30 minutes. A solution ofcarbonyldiimidazole (4.05 g, 25 mmol) in THF (40 mL) is added dropwiseover 20 minutes at −35° C. and then the cold bath is removed and thereaction mixture is stirred for 30 minutes. The reaction mixture istaken up in ethyl acetate and washed with aqueous 5% sodium bicarbonateand brine, dried over sodium sulfate, filtered, and concentrated invacuo. Chromatography on silica gel (30% acetone-hexane) gives thedehydrated compound (2.6 g) as a white foam. (M+H)⁺ is 744.

Step 4. Deprotection to Form Compound of Formula (1): L is CO, T is O,R_(a) is —CH₂CH═CH₂, R_(c) is H.

A solution of the compound resulting from step 3 (719 mg, 1.0 mmol) inmethanol (20 mL) is stirred at reflux for 6 hours. The reaction mixtureis concentrated in vacuo and the residue is purified by chromatographyon silica gel (95:5:0.5 dichloromethane-methanol-ammonia) to give thedesired compound.

Example 17 Compound of Formula (1): L is CO, T is O, R_(a) is—CH₂CH═CH-Phenyl

A. Form Cyclic Carbonate of Compound of Formula (1) from IlustrativeScheme 5: R_(a) is —CH₂CH═CH-Phenyl, R_(c) is Benzoyl.

A solution of the compound prepared in Example 15, step K or otherembodiments wherein R_(d) is propyl, butyl, benzyl, vinyl, or3-hydroxybutyl (150 mg, 0.20 mmol) in THF (5 mL) is cooled to −35° C.and flushed with nitrogen. Lithium hexamethyldisilazide (1.0 M in THF,0.22 mL, 0.22 mmol) over 2 minutes at −35° C. The reaction mixture isstirred for 10 minutes at −35° C. and then a solution ofcarbonyldimidazole (162 mg, 1.00 mmol) in THF (3 mL) is added dropwiseover 2 minutes. The cold bath is removed and the reaction mixture isstirred for 30 minutes. The reaction mixture is cooled to 0° C. andaqueous 0.5 M KH₂PO₄ is added. The mixture is extracted with ethylacetate and the organic phase is washed with brine, dried over sodiumsulfate, and concentrated in vacuo. Chromatography on silica gel (30%acetone-hexane) gives the dehydrated compound.

B. Deprotection to Form Compound of Formula (1): L is CO, T is O, R_(a)is —CH₂CH═CH-Phenyl, R_(c) is H

Deprotection of the compound prepared in step A is accomplished byheating in methanol according to the procedure of Example 16, step 4.

Using the procedures described in the preceding examples and schemes andmethods known in the synthetic organic chemistry art, the compounds ofFormula (1) wherein L is CO and T is O can be prepared. These compoundsinclude one of the R_(a) substituents listed below:

—CH₂CH₂CH₃ —CH₂CH₂NH₂ —CH₂CH═NOH —CH₂CH₂CH₂OH —CH₂F —CH₂CH₂-phenyl—CH₂CH₂-(4-pyridyl) —CH₂CH₂-(4-quinolyl) —CH₂CH(OH)CN—CH(C(O)OCH₃)CH₂-phenyl —CH₂CN —CH₂CH═CH-(4-methoxyphenyl)—CH₂CH═CH-(4-fluorophenyl) —CH₂CH═CH-(8-quinolyl) —CH₂CH₂NHCH₂-phenyl—CH₂-phenyl —CH₂-(4-pyridyl) —CH₂-(4-quinolyl) —CH₂CH═CH-(4-pyridyl)—CH₂CH₂CH₂-(4-pyridyl) —CH₂CH═CH-(4-quinolyl) —CH₂CH₂CH₂-(4-quinolyl)—CH₂CH═CH-(5-quinolyl) —CH₂CH₂CH₂-(5 quinolyl)—CH₂CH═CH-(4-benzoxazolyl) —CH₂CH═CH-(4-benzimidazolyl)

Example 18 Preparation of Compound of Formula (1): L is CO, T is NH,R_(a) is —CH₂CH═CH₂), R_(c) is H

Step 1: Preparation to Form 10, 11 Anhydro Form of Intermediate Compound(6): R_(a) is —CH₂CH═CH₂, R_(c) is Benzoyl.

A. 6-O-allyl-3-descladinosyl-15-methyl-erythromycin A

A mixture of 6-O-allyl-15-methylerythromycin A (6.58 g) and 125 mL of0.5 N HCl was stirred at ambient temperature for 20 hours. The pH wasadjusted to 10 by addition of 6 N NaOH, and the mixture was extractedthree times with 225-mL portions of ethyl acetate. The organic extractswere combined, washed sequentially with saturated NaHCO₃, water, andbrine, then dried over MgSO₄, filtered, and evaporated. The crudeproduct was chromatographed on silica gel (3:2 toluene/acetone +1% Et₃N)to yield 3.04 g of pure 6-O-allyl-3-descladinosyl-15-methylerythromycinA. ES-LC/MS shows [M+H]⁺=617.

B. 2′-O-Benzoyl-6-O-allyl-3-descladinosyl-15-methyl-erythromycin A

6-O-Allyl-3-descladinosyl-15-methylerythromycin A (2.43 g, 3.86 mmol,1.00 eq) and benzoic anhydride (1.78 g, 7.72 mmol, 2.00 eq) were placedin a round-bottomed flask and flushed with N₂. Ethyl acetate (17.5 mL)was added. The solution was stirred for 3.5 h and then diluted with 400mL of EtOAc and washed twice with 150 mL of saturated aqueous NaHCO₃ andonce each with 150 mL of water and brine. The organic phase was driedover MgSO₄, filtered, and concentrated. Purification by flashchromatography over silica gel (3:1 hexanes:acetone +1% Et₃N) gave 1.94g (68.1%) of the desired product as a white solid. ES-LC/MS shows[M+H]⁺=721. ¹³C NMR (100.6 MHz, CDCl₃) δ 219.4, 174.3, 165.4, 135.3,132.6, 130.8, 129.7, 128.2, 117.2, 99.7, 80.7, 79.0, 77.9, 77.7, 75.1,74.3, 72.3, 69.0, 64.7, 63.3, 45.6, 43.9, 40.7, 37.9, 37.7, 35.7, 32.1,30.8, 21.1, 20.2, 19.3, 18.1, 16.3, 15.1, 14.0, 12.4, 7.7.

C. 2′-O-Benzoyl-6-O-allyl-3-descladinosyl-3-oxo-15-methyl-erythromycin A

N-Chlorosuccinimide (0.510 g, 3.82 mmol, 1.50 eq) was dissolved in 13 mLof anhydrous CH₂Cl₂ and cooled to −10° C. under N₂. Methyl sulfide(0.328 mL, 4.46 mmol, 1.75 eq) was added, and the reaction was stirredfor 15 min. A solution of2′-O-benzoyl-6-O-allyl-3-descladinosyl-15-methylerythromycin A (1.87 g,2.55 mmol, 1.00 eq) in 13 mL of anhydrous CH₂Cl₂ was added dropwise.After 30 min, freshly distilled Et₃N (0.355 mL, 2.55 mmol, 1.00 eq) wasadded; and the reaction was brought up to 0° C. over 30 min. Thereaction mixture was diluted with 400 mL EtOAc and washed successivelywith 100 mL each of saturated aqueous NaHCO₃, water, and brine. Theorganic layer was dried over MgSO₄, filtered, concentrated, and purifiedby flash chromatography (9:1 hexanes:acetone +1% Et₃N) to give 0.931 g(49.9%) of the desired product as a white solid. ES-LC/MS shows[M+H]⁺=719. ¹³C NMR (100.6 MHz, CDCl₃) δ 219.1, 206.1, 169.5, 165.3,135.3, 132.7, 129.0, 129.7, 128.3, 117.4, 100.7, 78.5, 76.6, 75.3, 74.2,72.1, 69.2, 69.0, 64.5, 63.7, 50.6, 45.3, 44.8, 40.7, 38.3, 37.8, 31.7,31.0, 21.1, 20.2, 19.5, 18.1, 16.5, 14.5, 14.0, 12.6, 12.2.

D.2′-O-Benzoyl-6-O-allyl-3-descladinosyl-3-oxo-11-O-methanesulfonyl-15-methyl-erythromycinA

2′-O-Benzoyl-6-O-Allyl-3-descladinosyl-3-oxo-15-methylerythromycin A(904 mg, 1.24 mmol, 1.00 eq) was dissolved in freshly distilled pyridine(4 mL) and cooled to 0° C. Methanesulfonyl chloride (0.478 mL, 6.17mmol, 5.00 eq) was added dropwise. The reaction was allowed to come toambient temperature and stirred overnight. The mixture was diluted with350 mL of EtOAc and quenched with 100 mL of saturated aqueous NaHCO₃.The layers were separated, and the organic phase was washed successivelywith 100 mL each of water and brine. The organic phase was dried overMgSO₄, filtered, and concentrated. Flash chromatography over silica gel(4:1 hexanes:acetone +1% Et₃N) gave 741 mg (74.1%) of the desiredcompound as a white solid. ¹³C NMR (100.6 MHz, CDCl₃) δ 203.0, 168.9,165.0, 137.6, 133.1, 130.3, 129.8, 128.5, 114.4, 108.8, 102.2, 91.1,84.4, 81.6, 78.8, 72.2, 69.2, 64.3, 63.9, 52.1, 46.6, 45.8, 40.7, 38.8,38.2, 35.9, 31.8, 30.9, 29.7, 24.8, 21.0, 19.6, 18.2, 15.5, 15.4, 13.8,13.5.

E.2′-O-Benzoyl-6-O-allyl-3-descladinosyl-3-oxo-10,11-anhydro-15-methyl-erythromycinA

2′-O-Benzoyl-6-O-allyl-3-descladinosyl-3-oxo-11-methanesulfonyl-15-methyl-erythromycinA (705 mg, 0.870 mmol, 1.00 eq) was dissolved in acetone (3 mL), and1,8-diazabicyclo[5.4.0]undec-7-ene (0.651 mL, 4.35 mmol, 5.00 eq) wasadded dropwise. The reaction was stirred at ambient temperature for 6 hand then concentrated. Flash chromatography over silica gel (4:1hexanes:acetone +1% Et₃N) gave 486 mg (78.0%) of the desired compound asa white solid. ¹³C NMR (100.6 MHz, CDCl₃) δ 210.1, 208.4, 170.2, 165.2,141.0, 140.2, 136.3, 132.7, 130.4, 129.8, 128.2, 115.5, 100.6, 81.0,78.7, 77.2, 73.8, 72.0, 69.1, 64.6, 63.3, 51.0, 47.4, 40.8, 39.4, 36.2,31.9, 31.3, 23.6, 21.2, 21.1, 21.0, 19.4, 14.1, 13.9, 13.7, 13.1.

Step 2: Formation of Imidazolide Intermediate (7) from IllustrativeScheme 3 and Cyclization to Form Cyclic Carbamate of Compound (1)/(10):R_(a) is —CH₂CH═CH₂, R_(c) is benzoyl.

2′-O-Benzoyl-6-O-allyl-10,11-anhydro-3-descladinosyl-3-oxo-15-methyl-erythromycinA (227 mg, 0.317 mmol, 1.00 eq) was dissolved in 1.3 mL of freshlydistilled THF and cooled to −15° C. under N₂. Sodium hydride (25 mg of a60% dispersion in mineral oil, 0.634 mmol, 2.00 eq) was added, and thereaction was stirred for 15 min. A solution of 1,1-carbonyldiimidazole(140 mg, 0.866 mmol, 3.00 eq) in 1.3 mL of freshly distilled THF wasadded dropwise. After stirring for 30 min, the reaction was allowed towarm to ambient temperature over 1.5 h. The mixture was diluted with 100mL of EtOAc and washed successively with 30 mL each of saturated aqueousNaHCO₃, water, and brine. The organic phase was dried over MgSO₄,filtered, and concentrated to give 275 mg of crude product (100%) whichwas dissolved in 2 mL of ACN and 0.2 mL of anhydrous THF. Saturatedaqueous ammonium hydroxide (2 mL) was added. The reaction was sealed andstirred for 2 d. Volatiles were removed under reduced pressure, and theresidue was re-dissolved in 100 mL of EtOAc. The solution was washedsuccessively with 30 mL each of saturated aqueous NaHCO₃, water, andbrine. The organic phase was dried over MgSO₄, filtered, andconcentrated. Flash chromatography of the crude product (4:1hexanes:acetone +1% Et₃N) yielded 184 mg (76.5%) of the desired product.

Example 19 Preparation of Compound of Formula (3): L is CO, T is NH,R_(a) is —CH₂-(2-naphthyl)

Step 1: Alkylation of 6-OH to Form Compound (4) from Illustrative Scheme2: R_(a) is —CH₂-(2-naphthyl), R_(c) and R_(e) are H.

Following the procedures of Example 11, steps 1-3, except substituting(2-naphthyl)methyl bromide for the allyl bromide of step 1, the compoundis prepared.

Step 2: Protection of 2′,4″ Hydroxyls to Form Intermediate Compound (4)from Ilustrative Scheme 2: R_(a) is —CH₂-(2-naphthyl), R_(c) and R_(e)are Acetyl.

The compound from step 1 (2.0 g) is treated according to the procedureof Example 16, step 1, except substituting acetic anhydride for thebenzoic anhydride of that example.

Step 3: Formation of Intermediate Compound (9) from Illustrative Scheme2 and Formation of Cyclic Carbamate of Compound (3) from IllustrativeScheme 2:

The compound of step 2 (500 mg) is treated with NaH andcarbonyldiimidazole and is treated with ammonia in acetonitrileaccording to the procedure of Example 18, step 2 to afford the compound.

Example 20 Preparation of Compound of Formula (1): R_(c) is acetyl, isCO, T is NH, R_(a) is —CH₂CH═CH₂

Step 1. Preparation of Intermediate Compound (4) from IllustrativeScheme 2: R_(a) is —CH₂CH═CH₂, R_(c) and R_(e) are acetyl.

To a sample of the compound from Example 11, step 3 or an embodimentthereof wherein R_(d) is propyl, butyl, benzyl, vinyl or 3-hydroxybutyl(405.2 g, 528 mmol) in dichloromethane (20 mL) is addeddimethylaminopyridine (0.488 g, 4 mmol) and acetic anhydride (3.39 mL,36 mmol), and the mixture is stirred at room temperature for 3 hours.The mixture is diluted with methylene chloride, then washed with 5%aqueous sodium bicarbonate and brine and dried over Na₂SO₄. The residueis dried and recrystallized from acetonitrile to give the compound.

Step 2: Dehydration at C-10, 11 and Derivation of C-12 to FormIntermediate Compound (9) from Illustrative Scheme 2: R_(a) is—CH₂CH═CH₂, R_(c) and R_(e) are Acetyl.

To a sample of the compound from step 1 (85.8 g, 100 mmol) in dry THF(500 mL) cooled to −40° C. and flushed with nitrogen is added sodiumbis(trimethylsilyl)amide (125 mL, 125 mmol) over 20 minutes, and themixture is stirred at −40° C. for 40 minutes. To this mixture is added asolution of carbonyldiimidazole (3.65 g, 22.56 mmol) in 5:3 THF/DMF (800mL) under nitrogen at −40° C. over 30 minutes, and the mixture isstirred at −20° C. for 30 minutes. The mixture is stirred at roomtemperature for 27 hours, then diluted with ethyl acetate. The mixtureis washed with 5% sodium bicarbonate and brine, dried over Na₂SO₄, andconcentrated to give the compound (9), which is taken directly to thenext step.

Step 3: Formation of Cyclic Carbamate of Compound (3) from IllustrativeScheme 2: R_(a) is —CH₂CH═CH₂, R_(c) and R_(e) are Acetyl.

The compound from step 2 (124 g) is dissolved in 9:1 acetonitrile/THF(1100 mL), ammonium hydroxide (28%, 200 mL) is added, and the mixture isstirred at room temperature under nitrogen for 8 days. The solvent isremoved, and the residue is dissolved in ethyl acetate. This solution iswashed with 5% sodium bicarbonate and brine, dried over Na₂SO₄, andconcentrated to give compound (3).

Step 4: Preparation of 3-OH Form of Compound (1): R_(a) is —CH₂CH═CH₂,R_(c) and R_(e) are Acetyl.

To a sample of the compound from step 3 (69.0 g, 78.2 mmol) suspended inethanol (200 mL) and diluted with water (400 mL) is added HCl (0.972 N,400 mL) dropwise over 20 minutes. The mixture is stirred for 4 hours,and additional HCl is added (4 N, 100 mL) over 20 minutes. The mixtureis stirred for 18 hours, cooled to 0° C., then NaOH (4 N, 200 mL) isadded over 30 minutes to approximately pH 9. The intermediate compoundis isolated by filtration.

Step 5: Preparation of compound (1): R_(a) is —CH₂CH═CH₂,R_(c) and R_(e)are acetyl, L is CO, T is NH.

To a −10° C. solution under nitrogen of N-chlorosuccinimide (2.37 g,17.8 mmol) in dichloromethane (80 mL) is added dimethylsulfide (1.52 mL,20.8 mmol) over 5 minutes. The resulting white slurry is stirred for 10minutes at −10° C., a solution of the compound from step 4 (8.10 g, 11.9mmol) in dichloromethane (60 mL) is added and the reaction mixture isstirred for 30 minutes at −10 to −5° C. Triethylamine (1.99 mL, 14.3mmol) is added dropwise over 10 minutes and the reaction mixture isstirred for 1 hour at 0° C. The reaction mixture is extracted withdichloromethane. The organic phase is washed with aqueous 5% sodiumbicarbonate and brine, dried over sodium sulfate, and concentrated invacuo to give a white foam. Chromatography on silica gel (eluting with50:50:0.5 acetone/hexanes/ammonium hydroxide) gives the compound.

Example 21 Alternate preparation of compound of Formula (1): L is CO, Tis NH, R_(a) is —CH₂CH═CH-(3-quinolyl)

Step 1: Preparation of Compound of formula (1): R_(b) is H, R_(d) ispropyl, L is CO, T is NH, R_(a) is —CH₂CH═CH-(3-quinolyl)

Preparation A: Formula (1): R_(b)═H, R_(a) is —CH₂—CH═CH-(3-quinolyl)

2′-O-Benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycinA 11,12-cyclic carbamate (40 mg, 0.0528 mmol, 1.0 eq),tris(dibenzylideneacetone) dipalladium(O)-chloroform adduct (14 mg,0.014 mmol, 0.5 eq), tri-o-tolylphosphine (17 mg, 0.055 mmol, 1.0 eq),and 3-bromoquinoline (72 mL, 0.53 mmol, 10 eq) were placed in around-bottom flask which was flushed with N₂. Degassed acetonitrile (1mL) and freshly distilled Et₃N (0.015 ml, 0.11 mmol, 2.0 eq) were added.

The reaction was refluxed for 63 h. The mixture was returned to ambienttemperature and diluted with 40 mL of EtOAc. The solution was washedsuccessively with 10 mL each of saturated aqueous NaHCO₃, water, andbrine. The organic phase was dried over MgSO₄, filtered, andconcentrated. Flash chromatography of the crude product (gradient from5:1 to 2:1 hexanes:acetone+1% Et₃N) yielded 34 mg of the desiredproduct.

Step 2: The above product (34 mg) was dissolved in 1 mL of methanol,sealed, and refluxed at 80° C. for 16 h. Volatiles were removed underreduced pressure. Flash chromatography (1:1 hexanes:acetone+1% Et₃N)gave the desired product as a light yellow solid (25 mg, 61% over twosteps). ES-LC/MS: [M+H]⁺=780.5. ¹³C-NMR (CDCl₃, 100 MHz): δ217.44,205.37, 169.48, 157.69, 149.71, 147.61, 132.51, 129.96, 129.56, 129.15,129.05, 128.49, 128.05, 126.70, 102.90, 83.42, 78.71, 76.42, 75.91,70.22, 69.53, 65.83, 64.31, 58.12, 50.81, 46.29, 46.12, 45.05, 40.18(2C), 39.05, 37.31, 31.64, 28.19, 21.15, 20.18, 19.43, 18.05, 14.38,14.11, 13.76, 13.63 (2 C).

Preparation B: Formula (1): R_(b)=H, R_(a) is—CH₂—CH═CH-(3-(6-fluoroquinolyl)

This was prepared according to the method of Preparation A using3-bromo-6-fluoroquinoline in place of 3-bromoquinoline. ES-LC/MS:[M+H]⁺=798.5. ¹³C-NMR (CDCl₃, 100 MHz): δ 217.49, 205.36, 169.54, 160.6(J_(CF)=248 Hz), 157.68, 149.05, 144.69, 131.84, 131.64 (J_(CF)=9 Hz),130.28, 129.63, 129.31, 128.7 (J_(CF)=10 Hz), 119.20 (J_(CF)=27 Hz),110.87 (J_(CF)=22 Hz), 102.94, 83.42, 78.77, 76.44, 75.91, 70.22, 69.55,65.84, 64.24, 58.09, 50.83, 46.36, 46.06, 45.05, 40.18 (2 C) 39.04,37.32, 31.63, 28.19, 21.16, 20.19, 19.46, 18.04, 14.37, 14.18, 13.76,13.62 (2 C).

Preparation C: Formula (1): R_(b)=H, R_(a) is—CH₂—CH═CH-(3-(6-chloroquinolyl)

This is prepared according to the method of Preparation A using3-bromo-6-chloroquinoline in place of 3-bromoquinoline. ES-LC/MS:[M+H]⁺=814.5. ¹³C-NMR (CDCl₃, 100 MHz): δ 217.48, 205.35, 169.55,157.67, 149.90, 145.92, 132.42, 131.49, 130.80, 130.44, 129.92, 129.49,129.46, 128.71, 126.57, 102.94, 83.41, 78.78, 76.45, 75.91, 70.22,69.54, 65.83, 64.23, 58.07, 50.83, 46.39, 45.99, 45.04, 40.17 (2 C),39.03, 37.32, 31.62, 31.53, 28.18, 21.16, 20.17, 19.49, 18.04, 14.36,14.21, 13.76, 13.61 (2 C).

Preparation D: Formula (1): R_(b)=H, R_(a) is —CH₂—CH═CH-(4-isoquinolyl)

This was prepared according to the method of Preparation A using4-bromoisoquinoline in place of 3-bromoquinoline. ES-LC/MS: [M+H]⁺=781.¹³C-NMR (CDCl₃, 100 MHz): δ 217.19, 205.43, 169.75, 157.39, 152.07,140.74, 133.61, 130.65, 130.44, 128.07, 127.72, 127.05, 126.89, 122.77,102.85, 83.28, 78.74, 75.72, 70.22, 69.51, 65.88, 64.45, 58.10, 50.91,46.07, 45.09, 40.18 (2 C) 38.99, 37.34, 31.48, 29.66, 28.28, 21.18,20.39, 19.33, 14.53, 14.01, 13.86, 13.66, 13.62.

Preparation E: Formula (1): R_(b)=H, R_(a) is —CH₂—CH═CH-(3-pyridyl)

This was prepared according to the method of Preparation A using3-bromopyridine in place of 3-bromoquinoline. LC/MS: [M+H]⁺=731. ¹³C-NMR(CDCl₃, 100 MHz): δ 217.39, 205.27, 169.50, 157.61, 148.81, 148.68,132.63, 132.16, 129.65, 128.18, 123.46, 102.91, 83.36, 78.63, 76.35,75.79, 70.20, 69.52, 65.83, 64.17, 58.06, 50.78, 46.28, 45.03, 40.16 (2C), 38.96, 37.29, 31.64, 31.52, 28.19, 22.58, 21.14, 20.21, 19.42,18.04, 1.35, 14.12, 14.05, 13.79, 13.61 (2 C).

Preparation F: Formula (1): R_(b)=H, R_(a) is—CH₂—CH═CH-(3-(6-methylquinolyl)

This was prepared according to the method of Preparation A using3-bromo-6-methylquinoline in place of 3-bromoquinoline. ES-LC/MS:[M+H]⁺=795. ¹³C-NMR (CDCl₃, 100 MHz): δ 217.37, 205.35, 169.47, 157.65,148.82, 146.23, 136.45, 131.87, 131.37, 130.09, 129.51, 128.78, 128.22,128.06, 126.86, 102.87, 83.40, 78.68, 75.91, 70.20, 69.47, 65.83, 64.33,58.11, 50.81, 46.28, 45.04, 40.15 (2 C), 39.05, 37.31, 31.64, 28.24,21.52, 21.14, 20.18, 19.45, 18.05, 14.38, 14.11, 13.77, 13.63 (2 C).

Preparation G: Formula (1): R_(b)=H, R_(a) is—CH₂—CH═CH-(3-(6-aminoquinolyl)

This was prepared according to the method of Preparation A using3-bromo-6-aminoquinoline in place of 3-bromoquinoline. ES-LC/MS:[M+H]⁺=796.

Preparation H: Formula (1): R_(b)=H, R_(a) is—CH₂—CH═CH-(3-(5-isoxazol-3-yl)thienyl)

This is prepared according to the method of Preparation A, using5-(isoxazol-3-yl)-2-bromothiophene in place of 3-bromoquinoline.

Preparation I: Formula (1): R_(b)=H, R_(a) is —CH₂—CH═CH-(6-quinolyl)

This is prepared according to the method of Preparation A, using6-bromoquinoline in place of 3-bromoquinoline.

Preparation J: Formula (1): R_(b)=H, R_(a) is—CH₂—CH═CH-(3-quinoxal-6-yl)

This is prepared according to the method of Preparation A using6-bromoquinoxaline in place of 3-bromoquinoline.

Preparation K: Formula (1): R_(b)=H, R_(a) is—CH₂—CH═CH-(5-(N-(2-pyridyl)-2-furamidyl)

This is prepared according to the method of Preparation A, usingN-(2-pyridyl) 5-bromo-2-furamide in place of 3-bromoquinoline.

Preparation AA: Formula (1): R_(b)=F, R_(a) is —CH₂—CH═CH-(3-quinolyl)

This was prepared according to the method of Preparation A using2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-methylerythromycinA 11,12-cyclic carbamate in place of2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycinA 11,12-cyclic carbamate. LC/MS: [M+H]⁺=798.6. ¹⁹F-NMR (CDCl₃, 376 MHz):δ −163.93. ¹³C-NMR (CDCl₃, 100 MHz): δ 217.97, 204.28 (J_(CF)=27 Hz),165.62 (J_(CF)=23 Hz), 157.18, 149.71, 147.70, 132.65, 130.25, 129.53,129.22, 129.12, 129.06, 128.15, 128.08, 126.78, 104.10, 98.02(J_(CF)=206 Hz), 83.40, 79.59, 79.37, 77.57, 70.41, 69.74, 65.85, 64.36,58.11, 44.23, 40.83 (J_(CF)=1.5 Hz), 40.25 (2 C), 39.04, 37.45, 31.37,28.16, 25.30 (J_(CF)=22 Hz), 21.19, 20.86, 19.54, 17.67, 15.46(J_(CF)=1.7 Hz), 13.82, 13.80, 13.29.

Preparation BB: Formula (1): R_(b)=F, R_(a) is—CH₂—CH═CH-(3-(6-fluoroquinolyl)

This is prepared according to the method of Preparation B using2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-methylerythromycinA 11,12-cyclic carbamate in place of2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycinA 11,12-cyclic carbamate.

Preparation CC: Formula (1): R_(b)=F, R_(a) is—CH₂—CH═CH-(3-(6-chloroquinolyl)

This is prepared according to the method of Preparation C using2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-methylerythromycinA 11,12-cyclic carbamate in place of2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycinA 11,12-cyclic carbamate.

Preparation DD: Formula (1): R_(b)=F, R_(a) is—CH₂—CH═CH-(4-isoquinolyl)

This is prepared according to the method of Preparation D using2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-methylerythromycinA 11,12-cyclic carbamate in place of2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycinA 11,12-cyclic carbamate.

Preparation EE: Formula (1): R_(b)=F, R_(a) is —CH₂—CH═CH-(3-pyridyl)

This is prepared according to the method of Preparation E using2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-methylerythromycinA 11,12-cyclic carbamate in place of2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycinA 11,12-cyclic carbamate.

Preparation FF: Formula (1): R_(b)=F, R_(a) is—CH₂—CH═CH-(3-(6-methylquinolyl)

This is prepared according to the method of Preparation F using2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-methylerythromycinA 11,12-cyclic carbamate in place of2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycinA 11,12-cyclic carbamate.

Preparation GG: Formula (1): R_(b)=F R_(a) is—CH₂—CH═CH-(3-(6-aminoquinolyl)

This is prepared according to the method of Preparation G using2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-methylerythromycinA 11,12-cyclic carbamate in place of2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycinA 11,12-cyclic carbamate.

Preparation HH: Formula (1): R_(b)=F, R_(a) is—CH₂—CH═CH-(3-(5-isoxazol-3-yl)thienyl)

This is prepared according to the method of Preparation H using2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-methylerythromycinA 11,12-cyclic carbamate in place of2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycinA 11,12-cyclic carbamate.

Preparation II: Formula (1): R_(b)=F, R_(a) is —CH₂CH═CH-(6-quinolyl)

This is prepared according to the method of Preparation I using2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-methylerythromycinA 11,12-cyclic carbamate in place of2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycinA 11,12-cyclic carbamate.

Preparation JJ: Formula (1): R_(b)=F, R_(a) is—CH₂—CH═CH-(3-quinoxal-6-yl)

This is prepared according to the method of Preparation J using2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-methylerythromycinA 11,12-cyclic carbamate in place of2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycinA 11,12-cyclic carbamate.

Preparation KK: Formula (1): R_(b)=F, R_(a) is—CH₂—CH═CH-(5-(N-(2-pyridyl)-2-furamidyl)

This is prepared according to the method of Preparation K using2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-methylerythromycinA 11,12-cyclic carbamate in place of2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycinA 11,12-cyclic carbamate.

Using the procedures described in the preceding examples and schemes andmethods known in the synthetic organic chemistry art, the cycliccarbamate compounds of Formula (1) wherein L is CO and T is NH can beprepared. These compounds having the R_(a) substituent are describedbelow:

—CH₂CH═CH-phenyl —CH₂CH═CH-(3-quinolyl) —CH₂CH═CH₂ —CH₂CH₂CH₃—CH₂CH₂NH₂, —CH₂CH═NOH. —CH₂CH₂CH₂OH —CH₂F —CH₂CH₂NHCH₂-phenyl—CH₂CH₂NHCH₂-(4-pyridyl) —CH₂CH₂NHCH₂-(4-quinolyl) —CH₂CH(OH)CN—CH(C(O)OCH₃)CH₂-phenyl —CH₂CN —CH₂CH═CH-(4-chlorophenyl)—CH₂CH═CH-(4-fluorophenyl) —CH₂CH═CH-(4-methoxy-—CH₂CH₂CH₂-(4-ethoxyphenyl) phenyl) —CH₂CH═CH-(3-quinoly))—CH₂CH₂NHCH₂CH₂-(2- —CH₂-phenyl chlorophenyl) —CH₂-(4-quinolyl)—CH₂-(4-pyridyl) —CH₂CH₂CH₂-(4-pyridyl) —CH₂CH═CH-(4-pyridyl)—CH₂CH₂CH₂-(4-quinolyl) —CH₂CH═CH-(4-quinolyl) —CH₂CH₂CH₂-(5-quinolyl)—CH₂CH═CH-(5-quinolyl) —CH₂CH═CH-(4-benzimi- —CH₂CH═CH-(4-benzoxazolyl)dazolyl) —CH₂—CH═CH-(5-(3- —CH₂CH═CH-(8-quinolyl)isoxazolyl)-2-thiophenyl) —CH₂—CH═CH-(1,3-dimethyl-2,4-—CH₂-CH═CH═(5-(2- dioxo-5-pyrimidinyl) pyridyl)aminocarbonyl-2-furanyl)

Example 22 Preparation of compound of formula (1): L is CO, T is N(CH₃),R_(a) is —CH₂CH═CH₂, R_(c) is H

Step 1: Preparation of Compound (10) from Illustrative Scheme 3: R_(f)is methyl, R_(a) is —CH₂CH═CH₂, R_(c) is benzoyl.

Replacing the ammonium hydroxide of Example 18 with methylamine, theabove compound is formed.

Other Embodiments: Using the above procedures, compounds of formulas(1)-(3) can be formed wherein L is CO, T is: —N(CH₃); —NCH₂CH₂N(CH₃)₂;—N(CH₂CH═CH₂); —N(CH₂CH═CH-(3-quinolyl)); or —N(NH₂); and R_(a) is:—CH₂CH═CH-(3-quinolyl); —CH₂CH═CH₂; —CH₂CH₂CH₂-(3-quinolyl);—CH₂CH═CH-naphthyl; —CH₂CH═CH-(8-chloro-3-quinolyl);—CH₂CH═CH-(4-chloro-2-trifluoromethyl-6-quinolyl);—CH₂CH═CH-(2-fluorenyl); —CH₂CH═CH-(3-(2-furanyl)-6-quinolyl);—CH₂CH═CH-(9-fluorenone-2-yl); —CH₂CH═CH-(6-benzoyl-2-naphthyl);—CH₂CH═CH-(7-methoxy-2-naphthyl); —CH₂CH═CH-(3-phenyl-6-quinolyl);—CH₂CH═CH-(3-(2-pyridyl)-6-quinolyl);—CH₂CH═CH-(3-(2-thiophenyl)-6-quinolyl); —CH₂CH═CH-(4-methylnaphthyl);—CH₂CH═CH-(6-β-D-galactopyranosyl-2-naphthyl); —CH₂CH═CH-(7-quinolyl);—CH₂CH═CH-(4-fluoronaphthyl); —CH₂CH═CH-(3-biphenyl);—CH₂CH═CH-(5-nitronaphthyl); —CH₂CH═CH-(4-pyrrolylphenyl);—CH₂CH═CH-(6-methoxy-2-naphthyl); —CH₂CH═CH-(3,5-dichlorophenyl);—CH₂-(3-iodophenyl); —CH₂-(3-(2-furanyl)phenyl);—CH₂CH═CH-(6-hydroxy-2-naphthyl);—CH₂CH═CH-(6-(2-bromoethoxy)-2-naphthyl);—CH₂CH═CH-(6-(2-(tetrazolyl)ethoxy-2-naphthyl); —CH₂CH═CH-naphthyl;—CH₂CH═CH-(5-(3-isoxazolyl)-2-thiophenyl);—CH₂CH═CH-(1,3-dimethyl-2,4-dioxo-5-pyrimidinyl); and—CH₂CH═CH-(5-(2-pyridyl)aminocarbonyl-2-furanyl).

Further, following the procedures of Example 21, except substituting thereagent below for the 3-bromoquinoline of Example 21, additionalcompounds are prepared. These are compounds of Formula (1) wherein L isCO and T is O having the R_(a) substituent as described below:

Reagent R_(a) Substituent 2-bromonaphthalene —CH₂CH═CH-(2-naphthyl)4-bromo-1,2-methylenedioxy- —CH₂CH═CH-(3,4-methyl- benzeneenedioxyphenyl) 8-bromoquinoline —CH₂CH═CH-(8-quinolyl) 5-bromoindole—CH₂CH═CH-(5-indolyl) 3,4-ethylenedioxy-benzene —CH₂CH═CH-(3,4-ethyl-enedioxyphenyl) 1-iodo-3-nitrobenzene —CH₂CH═CH-(3-nitrophenyl)3-bromo-6-nitroquinoline —CH₂CH═CH-(6-nitroquinolyl) 5-bromoquinoline—CH₂CH═CH-(5-quinolyl) 2-methyl-6-bromoquinoline —CH₂CH═CH-(2-methyl-(6-quinolyl) 3-bromoquinoline *Compound of Formula (1): L is CO, T is NH,R_(c) is acetyl; R_(a) is —CH₂CH═CH-(3-quinolyl) 5-bromoisoquinoline—CH₂CH═CH-(5-isoquinolyl) 6-bromo-7-nitro-quinoxaline—CH₂CH═CH-(7-nitro-6- quinoxalinyl) 3-bromo-1,8-naphthyridine—CH₂CH═CH-(1,8-naphthyridin- 3-yl) 6-(acetylamino)-3-bromoquinoline—CH₂CH═CH-(6-(acetylamino)-3- quinolyl) 3-bromocarbazole—CH₂CH═CH-(3-carbazolyl) 5-bromobenzimidazole—CH₂CH═CH-(5-benzimidazolyl) 7-bromo-3-hydroxy-N-(2-—CH₂CH═CH-(-3-hydroxy-2- methoxyphenyl)-2-napthylamide(N-(2-methoxyphenyl)amido)-7- naphthyl) 6-bromoquinoxaline—CH₂CH═CH-(6-quinoxalinyl) 3-bromo-6-hydroxylquinoline—CH₂CH═CH-(6-hydroxy-3- quinolyl) 3-bromo-6-methoxyquinoline—CH₂CH═CH-(6-methoxy-3- quinolyl) 3-bromo-5-nitroquinoline—CH₂CH═CH-(5-nitro-3-quinolyl) 3-bromo-8-nitroquinoline—CH₂CH═CH-(8-nitro-3-quinolyl) 2-chloroquinoline —CH₂CH═CH-(2-quinolyl)4-chloroquinoline —CH₂CH═CH-(4-quinolyl) 3-bromoquinoline-6-carboxylic—CH₂CH═CH-(4-carboxyl-3- acid quinolyl) 3-bromoquinoline-6-carboxylic—CH₂CH═CH-(6-methoxycarbonyl- acid methyl ester 3-quinolyl)3-bromoquinoline-6-carboxamide —CH₂CH═CH-(6-aminocarbonyl-3- quinolyl)3-bromo-6-cyanoquinoline —CH₂CH═CH-(6-cyano-3- quinolyl)3-bromo-6-iodoquinoline —CH₂CH═CH-(3-bromo-6- quinolyl) *withoutdeprotection step

Example 23 Conversion at —OR_(a)

A. Allyl→—CH₂CHO

The compound from Example 18 (14.0 g) is dissolved in CH₂Cl₂ (200 mL)and the solution is cooled to −78° C. under a nitrogen atmosphere. Ozoneis then bubbled through the solution until a blue color persisted. Thereaction is then purged with N₂ until colorless and dimethylsulfide (14mL) is added, and the reaction mixture is warmed to 0° C. After stirringfor 90 min, the reaction mixture is concentrated under reduced pressureto give a light-yellow foam. This material is dissolved in THF (300 mL)and treated with triphenylphosphine (8 g) at reflux for 6 hours, thenthe reaction mixture is concentrated under reduced pressure.Chromatography (1:1 acetone/hexanes to 3:1 acetone/hexanes with 0.5%TEA) gave the product.

B. —CH₂CHO→—CH₂CH₂NHCH₂Phenyl

The compound from Example 23A (120 mg, 0.187 mmol) and benzylamine (40μL, 0.366 mmol, 2 equiv) are dissolved in 3 mL of dry dichloromethane.Molecular sieves (4 Å) are added and the reaction is stirred overnight.The reaction is then filtered and concentrated under reduced pressure.The resulting imine is dissolved in MeOH (5 mL), a catalytic amount of10% Pd on carbon is added, and the reaction is stirred rapidly under 1atm of H₂ pressure for 20 hours. The mixture is then filtered through aCelite pad, and the solution concentrated under reduced pressure.Chromatography (SiO₂, 5% MeOH/dichloromethane with 0.2% NH₄OH) gives thedesired material (84 mg) as a white solid.

C. —CH₂CHO→—CH₂CH₂NHCH₂CH₂Phenyl

This compound is prepared from the compound of Example 23A (108 mg,0.169 mmol) and phenethylamine (42 μL, 0.334 mmol, 2 equiv) using theprocedure described for Example 23B. Chromatography (SiO₂, 5%MeOH/dichloromethane with 0.5% NH₄OH) gives the desired material.

D. —CH₂CHO→—CH₂CH₂NHCH₂CH₂CH₂Phenyl

This compound is prepared from the compound of Example 23A (100 mg,0.156 mmol) and 3-phenyl-1-propylamine (40 μL, 0.282 mmol, 1.8 equiv)using the procedure described for Example 23B. Chromatography (SiO₂, 5%MeOH/dichloromethane with 0.5% NH₄OH) gives the desired material.

E. —CH₂CHO→—CH₂CH₂NHCH₂CH₂CH₂Phenyl

This compound is prepared from the compound of Example 23A (170 mg,0.266 mmol) and 4-phenyl-1-butylamine (68 μL, 0.431 mmol, 1.6 equiv)using the procedure described for Example 23B. Chromatography (SiO₂, 5%MeOH/dichloromethane with 0.2% NH₄OH) gives the desired material.

F. —CH₂CHO→—CH₂CH₂NHCH₂CH₂-(3-quinolyl)

The compound from Example 23A (135 mg, 0.211 mmol) and3-(3-quinolyl)-1-propylamine (70 mg, 0.376 mmol, 1.8 equiv) aredissolved in 4 mL of dry dichloromethane. Molecular sieves (4A) areadded and the reaction is stirred overnight. The reaction is thenfiltered and concentrated under reduced pressure. The resulting imine isdissolved in MeOH (5 mL) and treated with NaCNBH₃ (about 100 mg) andenough AcOH to turn bromocresol green indicator from blue to yellow.After stirring for 4 hours, the reaction mixture is poured intosaturated NaHCO₃ solution and extracted into dichloromethane. Theorganic portion is washed with saturated NaHCO₃, H₂O and brine, dried(Na₂SO₄) and concentrated under reduced pressure. Chromatography (SiO₂,5% MeOH/dichloromethane with 0.5% NH₄₀H to 10% MeOH/dichloromethane with1% NH₄OH) gives the desired material.

G. —CH₂CHO→—CH₂CH₂NHCH₂(3-quinolyl)

The title compound is prepared from the compound of Example 23A (150 mg,0.234 mmol) and 3-(aminomethyl)quinoline (100 mg, 0.633 mmol, 2.7 equiv)using the procedure described for Example 23F. Chromatography (SiO₂, 5%MeOH/dichloromethane with 0.5% NH₄OH) gives the desired material

The 3-(aminomethyl)quinoline reagent is prepared by methods known in theart.

Other embodiments of the formulas (1)-(3) wherein R_(b) is H, R_(c) isH, L is —CO—, T is —NH—, and R_(d) is propyl, butyl, benzyl, vinyl, or3-hydroxy butyl are those wherein R_(a) is converted from —CH₂CHO to:—CH₂CH₂NHCH₂(6-quinolyl); —CH₂CH═NO(phenyl); —CH₂CH═NOCH₂(phenyl);—CH₂CH═NOCH₂(4-NO₂-phenyl); —CH₂CH═NOCH₂(4-quinolyl);—CH₂CH═NOCH₂(2-quinolyl); —CH₂CH═NOCH₂(3-quinolyl);—CH₂CH═NOCH₂(6-quinolyl); —CH₂CH═NOCH₂(1-naphthyl);—CH₂CH═NOCH₂(2-naphthyl); —CH₂CH₂NHOCH₂(phenyl);—CH₂CH₂NHOCH₂(4-NO₂-phenyl); —CH₂C(O)-phenyl; —CH₂C(O)-(4-F-phenyl);—CH₂CH═NNHC(O)phenyl; or —CH₂CH(OH)-phenyl.

H. —CH₂CH═CH-(3-quinolyl) —CH₂CH₂CH₂(3-quinolyl)

A mixture of the compound from Example 18 where R_(a) is—CH₂CH═CH-(3-quinolyl) (230 mg) and 10% Pd/C (50 mg) in 30 mL ofmethanol and 15 mL of ethyl acetate is flushed with nitrogen and stirredunder 1 atm of hydrogen at room temperature for 22 hours. The mixture isfiltered, and the filtrate is concentrated under reduced pressure.Chromatography on silica gel (5% MeOH/dichloromethane with 0.5% NH₄OH)gives the desired material.

I. —CH₂CH═CH-(3-quinolyl)→—CH₂(2-(3-quinolyl)cyclopropyl)

To a solution of diazomethane (0.64 M, 3.12 mL, 2.00 mmol) in ether isadded a solution of the compound from Example 18 wherein R_(a) is—CH₂CH═CH-(3-quinolyl) (153 mg, 0.200 mmol) in dichloromethane (5.0 mL)at 0° C. under nitrogen. A small amount (2 mg) of palladium acetate isadded, and the mixture is stirred for 20 minutes. Another portion ofdiazomethane (3 mL) is added, and the mixture is stirred for anotherhour. The solvents are evaporated, and the residue is purified bychromatography on silica gel (5% MeOH/dichloromethane with 0.5% NH₄OH)to give the title compound as a white solid.

Example 24 Conversions at R_(c)

A. —H→propanoyl (R_(a) is —CH₂CH═CH-(3-quinolyl))

To a solution of the compound from Example 18 converted at R_(a),wherein R_(a) is —CH₂CH═CH(3-quinolyl), (152 mg) in dichloromethane isadded propionic anhydride (52 μL) and triethylamine (56 μL), and themixture is stirred for 24 hours at room temperature. The mixture isdiluted with ethyl acetate, and this is washed with 5% NaHCO₃ solutionand brine, dried (Na₂SO₄) and concentrated under reduced pressure. Theresidue is chromatographed on silica gel (1:1 acetone/hexanes) to givethe title compound as a white foam.

B. —H→ethylsuccinoyl (R_(a) is —CH₂CH═CH-(3-quinolyl))

To a solution of the compound from Example 18 converted at R_(a),wherein R_(a) is —CH₂CH═CH-(3-quinolyl) (153 mg, 0.200 mmol) indichloromethane (10 mL) at 0° C. is added ethyl succinyl chloride (29μL) and triethylamine (56 μL), and the mixture is stirred for 24 hoursat room temperature. The mixture is diluted with ethyl acetate, and thisis washed with 5% NaHCO₃ solution and brine, dried (Na₂SO₄) andconcentrated under reduced pressure. The residue is chromatographed onsilica gel (1:1 acetone/hexanes) to give the title compound as a whitefoam.

Example 25 Preparation of Compound of Formula (1): L is CO, T is NH,R_(a) is —CH₂C═C—H, R_(c) and R_(e) are H

Step 1: Preparation of Intermediate of Compound (4): Position 9 isN—O—(1-isopropoxycyclohexyl), R_(a) is —CH₂C≡C—H, R_(c) and R_(e) aretrimethylsilyl.

To a solution under nitrogen of 2′,4″-bis-O-trimethylsilylerythromycin A9-[O-(1-isopropoxycyclohexyl)]oxime (100 g, 96.9 mmol, preparedaccording to the method of U.S. Pat. No. 4,990,602) in THF (200 mL) isadded anhydrous DMSO (200 mL) and the mixture is cooled to 0° C. To thissolution stirred under a N₂ atmosphere is added propargyl bromide (27mL, 240 mmol, 80 wt. % in toluene), followed by a solution of dry KOH(13.6 g, 240 mmol) in anhydrous DMSO (300 mL) over 25 minutes, and themixture is stirred vigorously for 1 hour at 0° C. Additional KOH (10.9g, 190 mmol) and propargyl bromide (21 mL, 190 mmol) is added, and themixture is stirred at 0° C. under N₂ for 1.5 hours. This addition of KOHand propargyl bromide is repeated 3 more times at 1.5 hour intervals.The mixture is then extracted with ethyl acetate, and the organic phasesare washed with water and brine and dried (MgSO₄). Removal of thesolvent under vacuum gives the crude product, which is taken directly tothe next step.

Step 2: Conversion of —N—O- (1-isopropoxycyclohexyl) at Position 9 to—NOH in Intermediate of Compound (4): R_(a) is, —CH₂C≡C—H.

To the compound from Step 1 (108 g) in CH₃CN (300 mL) is added water(150 mL) and acetic acid (glacial, 200 mL), and the mixture is stirredat room temperature for about 20 hours. The solvent is then removedunder vacuum at 40° C., and the residue is taken up in EtOAc and washedsuccessively with 5% Na₂CO₃ and brine. The organic phase is then driedover MgSO₄, filtered and concentrated to give the compound as a brownfoam, which is taken directly to the next step.

Step 3: Conversion of —NOH at Position 9 to ═O to Form IntermediateCompound (4): R_(a) is —CH₂C≡C—H.

The compound from Step 2 (74 g) is dissolved in ethanol (550 mL) anddiluted with water (550 mL). To this solution is added sodium nitrite(33 g, 0.48 mol), and the reaction mixture is stirred at roomtemperature for 15 minutes. Next is added 4M HCl (125 mL, 0.48 mol) atambient temperature over 15 minutes, the mixture is heated to 70° C. fortwo hours, then cooled to room temperature. The mixture is extractedwith ethyl acetate, and the organic phase is washed with 5% Na₂CO₃ andbrine, then dried over MgSO₄, filtered and concentrated. The crudeproduct is purified by chromatography on silica gel, eluting with 1%methanol/dichloromethane containing 0.5% ammonium hydroxide. Thecompound is crystallized from acetonitrile to give the compound.

Step 4: Protection of 2′ and 4″ Hydroxyl Groups to Form IntermediateCompound (4) from Illustrative Scheme 2: R_(c) and R_(e) are Acetyl,R_(a) is —CH₂C≡C—H.

To a solution of 19 grams (246 mmol) the compound from Step 3 inanhydrous dichloromethane (100 mL) is added 4-dimethylaminopyridine (105mg) and triethylamine (7.16 mL, 52 mmol). The mixture is cooled to about15° C. in a cold water bath, and acetic anhydride (5.5 mL, 59 mmol) isadded over 5 minutes. After stirring at 15° C. for 5 minutes, the coldwater bath is removed, and the reaction is stirred at ambienttemperature for 4 hours. The mixture is diluted with ethyl acetate andwashed successively with 5% aqueous sodium carbonate (twice), water(twice) and brine. The organic extracts are dried over magnesiumsulfate, filtered and concentrated in vacuo. Drying to constant weightwith high vacuum provided the compound.

Step 5: Dehydration at Position 10, 11 and Derivation at Position 12 toForm Intermediate Compound (9) from Illustrative Scheme 2: R_(c) andR_(e) are acetyl, R_(a) is —CH₂C≡C—H.

To a 0° C. solution of the compound from Step 4 (21 g, 24.5 mmol) in THF(128 mL) and dimethyl sulfoxide (48 mL) is added1,1′-carbonyldiimidazole (14.3 g, 88.3 mmol). After stirring for 5minutes, sodium hydride (60% dispersion in mineral oil, 1.3 g, 32.5mmol) is added portionwise over 1 hour under a nitrogen atmosphere.After complete addition, the cooling bath is removed, and the mixture isstirred at ambient temperature for 3.5 hours. The reaction is recooledto 0° C., diluted with ethyl acetate (400 mL), and quenched with 5%aqueous sodium bicarbonate (50 mL). The organic layers are washedsuccessively with water and brine, then dried over magnesium sulfate.The solution is filtered and the filtrate is concentrated in vacuo anddried to constant weight to afford the compound which is taken directlyto the next step.

Step 6: Form Cyclic Carbamate of Compound (3) from Illustrative Scheme2: R_(c) and R_(e) are Acetyl, R_(a) is —CH₂C≡C—H.

A pressure vessel containing the compound from Step 5 (23 g, 24 mmol) inacetonitrile (250 mL) is cooled to −78° C. An equal volume of liquidammonia (250 mL) is condensed into the reaction vessel which is thensealed and allowed to warm to ambient temperature with stirring. After20 hours the reaction is recooled to −78° C., the pressure vessel isopened and the reaction was allowed to warm to ambient temperature withstirring. When all the liquid ammonia had evaporated, the acetonitrileis removed in vacuo, and the residue is dried to constant weight toprovide the compound.

Step 7: Remove Position 3 Cladinose Moiety to Form Compound (1) Having aPosition 3 Hydroxyl Group: R_(c) is acetyl, R_(a) is —CH₂C≡C—H.

To a 0° C. suspension of the compound from Step 6 (21 g) in 1:1ethanol/water (200 mL) is added 4 M hydrochloric acid (125 mL) over 10minutes. After removing the cooling bath, the reaction solution isstirred at ambient temperature for 26 hours. The mixture is diluted withwater, cooled to 0° C. and made basic to pH 10 with 2N sodium hydroxide.The mixture is then extracted with ethyl acetate (400 mL), and theorganic layers are washed with brine. The organic extracts are driedover magnesium sulfate, filtered, and concentrated in vacuo. Drying toconstant weight provided 18 g of the crude product which is crystallizedfrom ethyl acetate/hexanes to give the pure compound.

Step 8: Oxidation of Position 3 Hydroxyl to Carbonyl of Compound (1):R_(c) acetyl, R_(a) is —CH₂C≡C—H.

To a −10° C. solution of N-chlorosuccinimide (2.3 g, 0.017 moles) indichloromethane (100 mL) is added methyl sulfide (1.47 mL, 0.021 moles)over 5 minutes. The reaction is stirred at −10° C. for 10 minutes. Asolution of the compound from Step 7 (8.3 g, 0.012 m) in dichloromethane(100 mL) is then added over 30 minutes, and the mixture is stirred for25 minutes at −10° C. Triethylamine (1.6 mL, 0.021 mol) is added over 5minutes, and the reaction is stirred at −10° C. for 50 minutes. Thereaction is then quenched with 5% aqueous sodium bicarbonate (50 mL),and extracted with dichloromethane (300 mL). The organic layers arewashed with 5% aqueous sodium bicarbonate followed by brine, dried overmagnesium sulfate, filtered, and concentrated in vacuo. The crudeproduct is purified on silica gel with column chromatography elutingsequentially with 30% acetone/hexanes followed by 50% acetone/hexanes toprovide the compound.

Step 9: Deprotection to Form Compound of Formula (1): L is CO, T is NH,R_(a) is —CH₂C≡C—H, R_(c) is H.

A sample (72 mg) of the compound from Step 8 is dissolved in methanol (8mL) and stirred at ambient temperature for 18 hours. After concentratingunder vacuum and drying to constant weight under high vacuum 65 mg ofthe pure title compound is obtained.

Optional Step: Conversion of R_(a) from —CH₂C≡C-(6-methoxy-2-naphthylbromonaphthalene) to —CH₂C≡C—Br to form compound (1): R_(a) is—CH₂C≡C—Br, R_(c) is cetyl.

To a solution under nitrogen of the compound of Example 25, Step 8 (100mg) in acetone (1 mL) is added acetic acid (8.4 μL) at ambienttemperature. A second solution containing N-bromosuccinimide (39 mg) andsilver nitrate (2.5 mg) in 1 mL of acetone is prepared and then stirredat room temperature under nitrogen for ten minutes and is cooled to 0°C. The first solution is then added to the second solution in oneportion, the cooling bath is removed, and the resulting reaction mixturestirred at room temperature under nitrogen for 2 hours. The reaction isthen diluted with ethyl acetate, saturated aqueous sodium bicarbonate isadded, and the mixture is stirred at room temperature overnight. Theorganic phase is separated, washed with brine and dried (MgSO₄). Thesolvent is removed, and the residue is purified by chromatography onsilica gel, eluting with 40% acetone/hexanes to give the compound. TheR_(c) group can be deprotected with methanol.

Example 26 Preparation of Compound of Formula (1): L is CO, T is NH,R_(a) is specified below, R_(c) is H, R_(b) is H, R_(d) is propyl I.Starting Material: Preparation of Compound of Formula (1): R_(b)=H,R_(a) is —O-propargyl

Step 1: A solution of 2′,4″-bis-O-trimethylsilyl-15-methylerythromycin A9-[O-(1-isopropoxycyclohexyl)]oxime (100 mg) in 0.1 mL oftetrahydrofuran, 0.1 mL of ether, and 0.1 mL of DMSO was cooled to 10°C. and treated with 0.028 mL of 3-bromo-1-(trimethylsilyl)-1-propyneunder inert atmosphere. A mixture of methylsulfoxide (0.19 mL) and 1.0 Mpotassium tert-butoxide in tetrahydrofuran (0.38 mL) was added at a rateof 2.0 molar equivalents of base per hour. Additional equivalents (0.014mL) of the TMS-propargyl bromide were added after 0.5 and 1 hours. Thereaction was monitored by thin-layer chromatography (silica gel, 10:1toluene/acetone), and was judged complete after addition of 2.3 molarequivalents of base. The reaction was diluted with 100 mL of ethylacetate and 30 mL of saturated NaHCO₃, and washed sequentially withsaturated NaHCO₃, water, and brine. The organic phase was dried withMgSO₄, filtered, and evaporated. The crude product was chromatographedon silica gel (40:1 hexanes/acetone +1% Et₃N) to yield partiallypurified6-O-(3-trimethylsilyl)propargyl-2′,4″-bis-O-trimethylsilyl-15-methylerythromycinA 9-[O-(1-isopropoxycyclohexyl)]oxime.

Step 2: A solution of the impure6-O-(3-trimethylsilyl)propargyl-2′,4″-bis-O-trimethylsilyl-15-methylerythromycinA 9-[O-(1-isopropoxycyclohexyl)]oxime from above (0.88 g) in 4.4 mL ofacetonitrile is treated with 2.2 mL of water and 2.5 mL of acetic acid,and stirred for 24 hours at ambient temperature. The mixture isconcentrated after addition of 2-propanol, then repeatedly afteraddition of toluene. This material is stirred with potassium carbonateand methanol (6 mL) for 2.5 hours. The mixture is diluted with ethylacetate (200 mL), and washed sequentially with saturated NaHCO₃, water,and brine. The organic phase is dried with MgSO₄, filtered, andevaporated to yield the product.

Step 3: A solution of the product from (iii) and sodium hydrosulfite(0.59 g) in 7 mL of 1:1 ethanol/water is placed under inert atmosphere.Formic acid (0.096 mL) is added dropwise, and the mixture is stirred at80° C. for 5 hours. After cooling to ambient temperature, the reactionis adjusted to pH 10 with 6 N NaOH and extracted three times with 150-mLportions of ethyl acetate. The organic extracts are combined and washedsequentially with saturated NaHCO₃, water, and brine. The organic phaseis dried with MgSO₄, filtered, and evaporated to yield6-O-propargyl-15-methylerythromycin A suitable for further conversion.Pure material can be prepared by chromatography on silica gel.

Step 4: A mixture of 6-O-propargyl-15-methylerythromycin A (0.40 g) and6 mL of 0.6 N HCl is stirred at ambient temperature for 17 hours. The pHis adjusted to 9 by addition of 6 N NaOH, and 150 mL of ethyl acetate isadded. The organic extracts are washed sequentially with saturatedNaHCO₃, water, and brine, then dried over MgSO₄, filtered, andevaporated to provide further product. The crude product ischromatographed on silica gel to give pure6-O-propargyl-3-descladinosyl-15-methylerythromycin A.

Step 5: A solution of6-O-propargyl-3-descladinosyl-15-methylerythromycin A (0.16 g) andbenzoic anhydride (0.12 g) in 1.3 mL of ethyl acetate is stirred for 17h, then washed sequentially with saturated NaHCO₃, water, and brine. Thesolution is dried over MgSO₄, filtered, and evaporated. The crudeproduct is chromatographed on silica gel to yield2′-O-benzoyl-6-O-propargyl-3-descladinosyl-15-methylerythromycin A.

Step 6: N-Chlorosuccinimide (0.510 g, 3.82 mmol, 1.50 eq) is dissolvedin 13 mL of anhydrous CH₂Cl₂ and cooled to −10° C. under N2. Methylsulfide (0.328 mL, 4.46 mmol, 1.75 eq) is added, and the reaction isstirred for 15 min. A solution of2′-O-benzoyl-6-O-propargyl-3-descladinosyl-15-methylerythromycin A (1.87g, 2.55 mmol, 1.00 eq) in 13 mL of anhydrous CH₂Cl₂ is added dropwise.After 30 min, freshly distilled Et₃N (0.355 mL, 2.55 mmol, 1.00 eq) isadded, and the reaction is brought up to 0° C. over 30 min. The reactionmixture is diluted with 400 mL EtOAc and washed successively with 100 mLeach of saturated aqueous NaHCO₃, water, and brine. The organic layer isdried over MgSO₄, filtered, concentrated, and purified bychromatography.

Step 7:2′-O-Benzoyl-6-O-propargyl-3-descladinosyl-3-oxo-15-methylerythromycin A(904 mg) is dissolved in freshly distilled pyridine (4 mL) and cooled to0° C. Methanesulfonyl chloride (0.478 mL, 6.17 mmol, 5.00 eq) is addeddropwise. The reaction is allowed to come to ambient temperature andstirred overnight. The mixture is diluted with 350 mL of EtOAc andquenched with 100 mL of saturated aqueous NaHCO₃. The layers areseparated, and the organic phase is washed successively with 100 mL eachof water and brine. The organic phase is dried over MgSO₄, filtered, andconcentrated. Flash chromatography over silica gel yields the product.

Step 8:2′-O-Benzoyl-6-O-propargyl-3-descladinosyl-3-oxo-11-methanesulfonyl-15-methyl-erythromycinA (705 mg) is dissolved in acetone (3 mL), and1,8-diazabicyclo[5.4.0]-undec-7-ene (0.651 mL, 4.35 mmol, 5.00 eq) isadded dropwise. The reaction is stirred at ambient temperature for 6 hand then concentrated. Flash chromatography over silica gel yields theproduct.

Step 9:2′-O-Benzoyl-6-O-propargyl-10,11-anhydro-3-descladinosyl-3-oxo-15-methylerythromycinA (227 mg) is dissolved in 1.3 mL of freshly distilled THF and cooled to−15° C. under N₂. Sodium hydride (25 mg of a 60% dispersion in mineraloil, 0.634 mmol, 2.00 eq) is added, and the reaction was stirred for 15min. A solution of 1,1-carbonyldiimidazole (140 mg) in 1.3 mL of freshlydistilled THF is added dropwise. After stirring for 30 min, the reactionis allowed to warm to ambient temperature over 1.5 h. The mixture isdiluted with 100 mL of EtOAc and washed successively with 30 mL each ofsaturated aqueous NaHCO₃, water, and brine. The organic phase is driedover MgSO₄, filtered, and concentrated, then the residue is dissolved in2 mL of ACN and 0.2 mL of anhydrous THF. Saturated aqueous ammoniumhydroxide (2 mL) is added. The reaction is sealed and stirred for 2days. Volatiles are removed under reduced pressure, and the residue isredissolved in 100 mL of EtOAc. The solution is washed successively with30 mL each of saturated aqueous NaHCO₃, water, and brine. The organicphase is dried over MgSO₄, filtered, and concentrated. Flashchromatography yields the cyclic carbamate product.

II. Preparation of Compounds using Compounds of I

Preparation A: Formula (1): R_(b)=H, R_(a) is —CH₂—CC-(3-quinolyl)

Step 1:2′-O-Benzoyl-6-O-propargyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycinA 11,12-cyclic carbamate (40 mg), tris(dibenzylideneacetone)dipalladium(0)-chloroform adduct (14 mg), tri-o-tolylphosphine (17 mg),copper iodide, and 3-bromoquinoline (72 μl, 0.53 mmol, 10 eq) are placedin a round-bottom flask which is flushed with N₂. Degassed acetonitrile(1 mL) and freshly distilled Et₃N (0.015 ml, 0.11 mmol, 2.0 eq) areadded. The reaction is refluxed for 63 h. The mixture is returned toambient temperature and diluted with 40 mL of EtOAc. The solution iswashed successively with 10 mL each of saturated aqueous NaHCO₃, water,and brine. The organic phase is dried over MgSO₄, filtered, andconcentrated. Flash chromatography yields the desired product.

Step 2: The above product is dissolved in 1 mL of methanol, sealed, andrefluxed at 80° C. for 16 h. Volatiles are removed under reducedpressure. Flash chromatography yields the desired product.

Preparation B: Formula (1): R_(b)=H, R_(a) is—CH₂—CC-(3-(6-fluoroquinolyl)

This is prepared according to the method of Preparation A, using3-bromo-6-fluoroquinoline in place of 3-bromoquinoline.

Preparation C: Formula (1): R_(b)=H, R_(a) is—CH₂—CC-(3-(6-chloroquinolyl)

This is prepared according to the method of Preparation A, using3-bromo-6-chloroquinoline in place of 3-bromoquinoline.

Preparation D: Formula (1): R_(b)=H, R_(a) is —CH₂—CC-(4-isoquinolyl)

This is prepared according to the method of Preparation A, using4-bromoisoquinoline in place of 3-bromoquinoline.

Preparation E: Formula (1): R_(b)=H, R_(a) is —CH₂—CC-(3-pyridyl)

This is prepared according to the method of Preparation A, using3-pyridine in place of 3-bromoquinoline.

Preparation F: Formula (1): R_(b)=H, R_(a) is—CH₂—CC-(3-(6-methylquinolyl)

This is prepared according to the method of Preparation A, using3-bromo-6-methylquinoline in place of 3-bromoquinoline.

Preparation G: Formula (1): R_(b)=H, R_(a) is—CH₂—CC-(3-(6-aminoquinolyl)

This is prepared according to the method of Preparation A, using3-bromo-6-aminoquinoline in place of 3-bromoquinoline.

Preparation H: Formula (1): R_(b)=H, R_(a) is—CH₂—CC-(3-(5-isoxazol-3-yl)thienyl)

This is prepared according to the method of Preparation A, using5-(isoxazol-3-yl)-2-bromothiophene in place of 3-bromoquinoline.

Preparation I: Formula (1): R_(b)=H, R_(a) is —CH₂—CC-(6-quinolyl)

This is prepared according to the method of Preparation A, using6-bromoquinoline in place of 3-bromoquinoline.

Preparation J: Formula (1): R_(b)=H, R_(a) is —CH₂—CC-(3-quinoxal-6-yl)

This is prepared according to the method of Preparation A using6-bromoquinoxaline in place of 3-bromoquinoline.

Preparation K: Formula (1): R_(b)=H, R_(a) is—CH₂—CC-(5-(N-(2-pyridyl)-2-furamidyl)

This is prepared according to the method of Preparation A, usingN-(2-pyridyl) 5-bromo-2-furamide in place of 3-bromoquinoline.

Preparation AA: Formula (1): R_(b)=F, R_(a) is —CH₂—CC-(3-quinolyl)

This was prepared according to the method of Preparation A using2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-methylerythromycinA 11,12-cyclic carbamate in place of2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycin A 11,12-cyclic carbamate.

Preparation BB: Formula (1): R_(b)=F, R_(a) is—CH₂—CC-(3-(6-fluoroquinolyl)

This is prepared according to the method of Preparation B using2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-methyletythromycinA 11,12-cyclic carbamate in place of2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo- 15-methylerythromycin A 11,12-cyclic carbamate.

Preparation CC: Formula (1): R_(b)=F, R_(a) is—CH₂—CC-(3-(6-chloroquinolyl)

This is prepared according to the method of Preparation C using2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-methylerythromycinA 11,12-cyclic carbamate in place of2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycinA 11,12-cyclic carbamate.

Preparation DD: Formula (1): R_(b)=F, R_(a) is —CH₂—CC-(4-isoquinolyl)

This is prepared according to the method of Preparation D using2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-methylerythromycinA 11,12-cyclic carbamate in place of2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycinA 11,12-cyclic carbamate.

Preparation EE: Formula (1): R_(b)=F, R_(a) is —CH₂—CC-(3-pyridyl)

This is prepared according to the method of Preparation E using2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-methylerythromycinA 11,12-cyclic carbamate in place of2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycinA 11,12-cyclic carbamate.

Preparation FF: Formula (1): Rb=F, R_(a) is—CH₂—CC-(3-(6-methylquinolyl)

This is prepared according to the method of Preparation F using2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-methylerythromycinA 11,12-cyclic carbamate in place of2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycinA 11,12-cyclic carbamate.

Preparation GG: Formula (1): R_(b)=F, R_(a) is—CH₂—CC-(3-(6-aminoquinolyl)

This is prepared according to the method of Preparation G using2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-methylerythromycinA 11,12-cyclic carbamate in place of2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycinA 11,12-cyclic carbamate.

Preparation HH: Formula (1): R_(b)=F, R_(a) is—CH₂—CC-(3-(5-isoxazol-3-yl thienyl)

This is prepared according to the method of Preparation H using2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-methylerythromycinA 11,12-cyclic carbamate in place of2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycinA 11,12-cyclic carbamate.

Preparation II: Formula (1): R_(b)=F, R_(a) is —CH₂—CC-(6-quinolyl)

This is prepared according to the method of Preparation I using2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-methylerythromycinA 11,12-cyclic carbamate in place of2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycinA 11,12-cyclic carbamate.

Preparation JJ: Formula (1): R_(b)=F, R_(a) is —CH₂—CC-(3-quinoxal-6-yl)

This is prepared according to the method of Preparation J using2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-methylerythromycinA 11,12-cyclic carbamate in place of2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycinA 11,12-cyclic carbamate.

Preparation KK: Formula (1): R_(b)=F, R_(a) is—CH₂—CC-(5-(N-(2-pyridyl)-2-furamidyl)

This is prepared according to the method of Preparation K using2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-methylerythromycinA 11,12-cyclic carbamate in place of2′-O-benzoyl-6-O-allyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-methylerythromycinA 11,12-cyclic carbamate.

Example 27 Compound of Formula (1): L is CO, T is NH, R_(a) is—CH₂-(2,2-dimethyl-1,3-dioxolan-4-yl), R_(c) is H

Step 1: Conversion of 3-OH Form of Compound (1) From R_(a) is —CH₂CH═CH₂to R_(a) is —CH₂CH(OH)CH₂OH, R_(c) is Acetyl.

To a sample of the compound from Example 20, Step 4 (5.0 g, 7.32 mmol,3-OH form of compound (1), R_(a) is —CH₂CH═CH₂, R_(c) is acetyl) andN-methylmorpholine N oxide (1.7 g, 14.5 mmol) in THF (25 mL) at roomtemperature is added OsO (4% in H₂O, 0.090 mL, 0.0147 mmol), and themixture is stirred for 24 hours. The reaction is quenched with sodiumbisulfite (1.5 g) and water (10 mL), and the solvents are removed undervacuum. The residue is dissolved in ethyl acetate, which is washed withsaturated aqueous sodium bicarbonate, water and brine, and dried(Na₂SO₄). The solvent is removed to give the compound.

Step 2: Conversion of 3-OH Form of Compound (1) From R_(a) is—CH₂CH(OH)CH₂OH to R_(a) is —CH₂-(2,2-dimethyl-1,3-dioxolan-4-yl), R_(c)is Acetyl.

To a sample of the compound from Step 1 (500 mg, 0.70 mmol) and2,2-dimethoxypropane (0.26 mL, 2.1 mmol) in toluene (7 mL) is addedp-toluenesulfonic acid (160 mg, 0.84 mmol), and the mixture is stirredat 55° C. for 3 days. The mixture is diluted with ethyl acetate, andthis solution is washed with 10% sodium carbonate solution, water andbrine. The organic phase is dried (Na₂SO₄), and the solvent is removedto give the crude product, which is purified by chromatography on silicagel, eluting with 2:97:1 methanol/chloroform/ammonium hydroxide to givethe compound.

Step 3: Oxidation of 3-OH to Carbonyl to Form Compound (1): R_(a) is—CH₂-(2,2-dimethyl-1,3-dioxolan-4-yl), R_(c) is Acetyl.

A sample of the compound from Step 2 (356 mg, 0.47 mmol) is oxidizedwith N-chlorosuccinimide and dimethylsulfide according to the procedureof Example 16, Step 2, to afford the compound.

Step 4: Deprotection to Form Compound of Formula (1): L is CO, T is NH,R_(a) is —CH₂(2,2-dimethyl-1,3-dioxolan-4-yl), R_(c) is H.

A sample of the compound from Step 3 (100 mg, 0.13 mmol) is stirred inmethanol (4 mL) overnight at room temperature. The solvent is removed,and the residue is purified by chromatography on silica gel, elutingwith 0.9:98:1 methanol/chloroform/ammonium hydroxide to give thecompound.

Optional Step: Conversion of R_(a) is—CH₂-(2,2-dimethyl-1,3-dioxolan-4-yl) in compound (1) to—CH₂CH(OH)CH₂OH.

A sample of the compound from Step 4 (100 mg, 0.13 mmol) is stirred atreflux with p-toluenesulfonic acid (35 mg, 0.18 mmol) in 4:1 THF/water(2.5 mL) for 3 hours. The mixture is diluted with ethyl acetate, andthis solution is washed with 10% sodium carbonate solution, water andbrine. The organic phase is dried (Na₂SO₄), and the solvent is removedto give the crude product, which is purified by chromatography on silicagel, eluting with 2:97:1 methanol/chloroform/ammonium hydroxide to givethe compound.

Example 28 Fluorination of C2 Position before 11,12 Cyclic Ring FormedSynthesis of2′-O-benzoyl-6-O-propargyl-3-descladinosyl-3-oxo-10,11-anhydro-2-fluoro-15-methylerythromycinA

A solution of2′-O-benzoyl-6-O-propargyl-3-descladinosyl-3-oxo-10,11-anhydro-15-methyl-erythromycinA in tetrahydrofuran under inert atmosphere is cooled to −78° C. andtreated with 1.0 M potassium tert-butoxide in tetrahydrofuran. Themixture is stirred for 5 minutes, and a solution ofN-fluorobenzenesulfonimide in tetrahydrofuran is added in three portionsover 2 hours. After addition, the reaction is allowed to warm to ambienttemperature and kept for an additional 5 hours. Aqueous K₂CO₃ is added,and the mixture is extracted with CH₂Cl₂. The organic extracts arecombined, dried over MgSO₄, filtered, and evaporated. Chromatography onsilica gel gives the product.

Example 29 Fluorination of C2 Position after Cyclic Carbamate FormedSynthesis of2′-O-benzoyl-6-O-allyl-3-descladinosyl-3-oxo-11-deoxy-11-amino-2-fluoro-15-methylerythromycinA 11,12 cyclic carbamate

To a THF solution (0.5 ml) of2′-O-benzoyl-6-O-allyl-3-descladinosyl-3-oxo-11-deoxy-11-amino-15-methylerythromycinA 11,12-cyclic carbamate (100 mg, 0.132 mmol, 1.0 eq) was added a THFsolution of potassium tert-butoxide (0.3 ml, 1M, 2.3 eq.) at −78° C. Thereaction mixture was then kept at −60° C. to −40° C. for 20 min.,followed by introduction of N-Fluorobenzenesulfonimide (46 mg, 0.146mmol, 1.1 eq.) in THF (0.2 ml) at −78° C. The reaction mixture was keptat −70° C. to −40° C. for 1 h before it was allowed to warm to 0° C.from −70° C. in 1.5 h. It was then diluted with EtOAc, washed withsaturated aqueous NaHCO₃, water, and brine. The organic phase was driedover MgSO₄, filtered, and concentrated. Flash chromatography of thecrude product (4:1 hexanes:acetone +1% Et₃N) yielded 76 mg (74%) of thedesired product. ¹³C-NMR (100.6 MHz, CDCl₃) δ 217.5, 203 (d, J=27.6 Hz),165.5 (d, J=23.8 Hz), 165.2, 157.5, 135.4, 132.9, 130.4, 129.8, 128.3,118.0, 101.7, 98 (d, J=207 Hz), 83.5, 79.1, 78.6, 72.1, 69.4, 64.6,63.5, 57.5, 44.2, 40.7, 40.4, 38.5, 37.3, 31.4, 31.3, 24.9 (d, J=24.3Hz), 21.0, 20.7, 19.4, 17.7, 15.0, 13.9, 13.7, 13.3.

Example 30 Derivatization of C-13 Position Starting Material:15-Aminoerythromycin A diacetate salt

A solution of 15-azidoerythromycin A (7.75 g, 10 mmol) in 50 mL ofmethanol is treated with acetic acid (2.0 mL) and 10% palladium oncarbon (0.1 g) and stirred under 1 atm of hydrogen gas until thin-layerchromatographic analysis reveals complete reduction of the startingmaterial. The suspension is filtered through Celite to remove thecatalyst, then evaporated to dryness to yield the product, which is usedas a starting material for the following derivatizations.

A. Synthesis of 15-(quinol-4-ylacetamido)erythromcin A

A solution of 15-aminoerythromycin A diacetate salt (1.0 g) in 10 mL ofdichloromethane is treated sequentially with quinol-4-ylacetyl chloride(350 mg) and triethylamine (0.5 mL) at 0° C. After 3 hours, the reactionis diluted with dichloromethane and washed three times with saturatedaqueous NaHCO₃. The organic phase is dried over MgSO₄, filtered, andevaporated to yield the crude product. Purification by silica gelchromatography yields the pure product.

B. Synthesis of 15-(3-(quinol-4-yl)propionamido)erythromycin A

A solution of 15-aminoerythromycin A diacetate salt (1.0 g) in 10 mL ofdichloromethane is treated sequentially with 3-(quinol-4-yl)propionylchloride (400 mg) and triethylamine (0.5 mL) at 0° C. After 3 hours, thereaction is diluted with dichloromethane and washed three times withsaturated aqueous NaHCO₃. The organic phase is dried over MgSO₄,filtered, and evaporated to yield the crude product. Purification bysilica gel chromatography yields the pure product.

C. Synthesis of 15-(isoquinol-4-ylacetamido)erythromycin A

A solution of 15-aminoerythromycin A diacetate salt (1.0 g) in 10 mL ofdichloromethane is treated sequentially with isoquinol-4-ylacetylchloride (350 mg) and triethylamine (0.5 mL) at 0° C. After 3 hours, thereaction is diluted with dichloromethane and washed three times withsaturated aqueous NaHCO₃. The organic phase is dried over MgSO₄,filtered, and evaporated to yield the crude product. Purification bysilica gel chromatography yields the pure product.

D. Synthesis of 15-(3-(isoquinol-4-yl)propionamido)erythromycin A

A solution of 15-aminoerythromycin A diacetate salt (1.0 g) in 10 mL ofdichloromethane is treated sequentially with 3-(isoquinol-4-yl)propionylchloride (400 mg) and triethylamine (0.5 mL) at 0° C. After 3 hours, thereaction is diluted with dichloromethane and washed three times withsaturated aqueous NaHCO₃. The organic phase is dried over MgSO₄,filtered, and evaporated to yield the crude product. Purification bysilica gel chromatography yields the pure product.

E. Synthesis of 15-((quinol-5-ylamino)acetamido)erythromycin A

A solution of 15-aminoerythromycin A diacetate salt (1.0 g) in 10 mL ofdichloromethane is treated sequentially with (quinol-5-ylamino)aceticacid (0.30 g), dicyclohexylcarbodiimide (0.4 g), 1-hydroxybenzotriazole(0.25 g), and triethylamine (0.5 mL) at 0° C. After 3 hours, thereaction is diluted with dichloromethane and washed three times withsaturated aqueous NaHCO₃. The organic phase is dried over MgSO₄,filtered, and evaporated to yield the crude product. Purification bysilica gel chromatography yields the pure product.

F. Synthesis of 15-((quinol-6-ylamino)acetamido)erythromycin A

A solution of 15-aminoerythromycin A diacetate salt (1.0 g) in 10 mL ofdichloromethane is treated sequentially with (quinol-6-ylamino)aceticacid (0.30 g), dicyclohexylcarbodiimide (0.4 g), 1-hydroxybenzotriazole(0.25 g), and triethylamine (0.5 mL) at 0° C. After 3 hours, thereaction is diluted with dichloromethane and washed three times withsaturated aqueous NaHCO₃. The organic phase is dried over MgSO₄,filtered, and evaporated to yield the crude product. Purification bysilica gel chromatography yields the pure product.

G. Synthesis of 15-((quinol-4-ylmethyl)carbamoylamino)erythromycin A

A solution of 15-aminoerythromycin A diacetate salt (1.0 g) in 10 mL ofdichloromethane is treated sequentially with quinoline-4-methoxycarbonylchloride (400 mg) and triethylamine (0.5 mL) at 0° C. After 3 hours, thereaction is diluted with dichloromethane and washed three times withsaturated aqueous NaHCO₃. The organic phase is dried over MgSO₄,filtered, and evaporated to yield the crude product. Purification bysilica gel chromatography yields the pure product.

Example 316-O-Methyl-3-descladinosyl-3-oxo-11-deoxy-11-amino-15-(3-(quinol-4-yl)propionamido)erythromycinA 11,12-cyclic carbamate

This is prepared according to the procedures described in Example 30,starting with 15-(3-(quinol-4-yl)propionamido)erythromycin A.

Example 326-O-Methyl-3-descladinosyl-3-oxo-11-deoxy-11-amino-2-fluoro-15-(3-(quinol-4-yl)propionamido)erythromycinA 11,12-cyclic carbamate

Step 1. To a solution of2′-O-benzoyl-6-O-methyl-3-descladinosyl-3-oxo-11-deoxy-11-amino-15-(3-(quinol-4-yl)propionamido)erythromycinA 11,12-cyclic carbamate in THF is added a TBE solution of potassiumtert-butoxide (2.3 eq.) at −78° C. The reaction mixture is then kept at−60° C. to −40° C. for 20 min., followed by introduction ofN-Fluorobenzenesulfonimide (1.1 eq.) in THF (0.2 ml) at −78° C. Thereaction mixture is kept at −70° C. to −40° C. for 1 h before it isallowed to warm to 0° C. from −70° C. in 1.5 h. It is then diluted withEtOAc, washed with saturated aqueous NaHCO₃, water, and brine. Theorganic phase is dried over MgSO₄, filtered, and concentrated. Flashchromatography yields the desired product as the 2′-O-benzoate.

Step 2. The product of Step 1 is dissolved in 1 mL of methanol, sealed,and refluxed at 80° C. for 16 h. Volatiles are removed under reducedpressure. Flash chromatography yields the desired product.

Example 332′-O-Benzoyl-6-O-methyl-3-descladinosyl-3-oxo-11-deoxy-11-amino-15-ethenylerythromycinA 11,12-cyclic carbamate

This is prepared according to the procedures described previously,starting with 15-ethenylerythromycin A.

Example 346-O-methyl-3-descladinosyl-3-oxo-11-deoxy-11-amino-15-ethenylerythromycinA 11,12-cyclic carbamate

2′-O-Benzoyl-6-O-methyl-3-descladinosyl-3-oxo-11-deoxy-11-amino-15-ethenylerythromycinA 11,12-cyclic carbamate from Example 33 is dissolved in 1 mL ofmethanol, sealed, and refluxed at 80° C. for 16 h. Volatiles are removedunder reduced pressure. Flash chromatography yields the desired product.

Example 356-O-Methyl-3-descladinosyl-3-oxo-11-deoxy-11-amino-2-fluoro-15-ethenylerythromycinA 11,12-cyclic carbamate

Step 1. To a solution of2′-O-benzoyl-6-O-methyl-3-descladinosyl-3-oxo-11-deoxy-11-amino-15-ethenylerythromycinA 11,12-cyclic carbamate in THF is added a THF solution of potassiumtert-butoxide (2.3 eq.) at −78° C. The reaction mixture is then kept at−60° C. to 40° C. for 20 min., followed by introduction ofN-Fluorobenzenesulfonimide (1.1 eq.) in THF (0.2 ml) at −78° C. Thereaction mixture is kept at −70° C. to −40° C. for 1 h before it isallowed to warm to 0° C. from −70° C. in 1.5 h.

It is then diluted with EtOAc, washed with saturated aqueous NaHCO₃,water, and brine. The organic phase is dried over MgSO₄, filtered, andconcentrated. Flash chromatography yields the desired product as the2′-O-benzoate.

Step 2. The product of Step 1 is dissolved in 1 mL of methanol, sealed,and refluxed at 80° C. for 16 h. Volatiles are removed under reducedpressure. Flash chromatography yields the desired product.

Example 366-O-Methyl-3-descladinosyl-3-oxo-11-deoxy-11-amino-15-(2-(3-quinolylethenyl erythromycin A 11,12-cyclic carbamate

Step 1:2′-O-Benzoyl-6-O-methyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-15-ethenylerythromycinA 11,12-cyclic carbamate (40 mg), tris(dibenzylideneacetone)dipalladium(0)-chloroform adduct (14 mg), tri-o-tolylphosphine (17 mg),and 3-bromoquinoline (72 μl) are placed in a round-bottom flask which isflushed with N₂. Degassed acetonitrile (1 mL) and freshly distilled Et₃N(0.015 ml) are added. The reaction is refluxed for 63 h. The mixture isreturned to ambient temperature and diluted with 40 mL of EtOAc. Thesolution is washed successively with 10 mL each of saturated aqueousNaHCO₃, water, and brine. The organic phase is dried over MgSO₄,filtered, and concentrated. Flash chromatography of the crude productyields the desired product.

Step 2: The product of Step 1 is dissolved in 1 mL of methanol, sealed,and refluxed at 80° C. for 16 h. Volatiles are removed under reducedpressure. Flash chromatography yields the desired product.

Example 376-O-Methyl-3-descladinosyl-3-oxo-11-deoxy-11-amino-2-fluoro-15-(2-(3-quinolyl)ethenyl)erythromycinA 11,12-cyclic carbamate

Step 1:2′-O-Benzoyl-6-O-methyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-ethenylerythromycinA 11,12-cyclic carbamate (40 mg), tris(dibenzylideneacetone)dipalladium(0)-chloroform adduct (14 mg), tri-o-tolylphosphine (17 mg),and 3-bromoquinoline (72 μl) are placed in a round-bottom flask which isflushed with N₂. Degassed acetonitrile (1 mL) and freshly distilled Et₃N(0.015 ml) are added. The reaction is refluxed for 63 h. The mixture isreturned to ambient temperature and diluted with 40 mL of EtOAc. Thesolution is washed successively with 10 mL each of saturated aqueousNaHCO₃, water, and brine. The organic phase is dried over MgSO₄,filtered, and concentrated. Flash chromatography of the crude productyields the desired product.

Step 2: The product of Step 1 is dissolved in 1 mL of methanol, sealed,and refluxed at 80° C. for 16 h. Volatiles are removed under reducedpressure. Flash chromatography yields the desired product.

Example 386-O-Methyl-3-descladinosyl-3-oxo-11-deoxy-11-amino-2-fluoro-15-(2-(3-quinolylmethylethenyl erythromycin A 11,12-cyclic carbamate

Step 1: A mixture of2′-O-benzoyl-6-O-methyl-11-amino-3-descladinosyl-11-deoxy-3-oxo-2-fluoro-15-ethenylerythromycinA 11,12-cyclic carbamate, 3-allylquinoline, andbis(triphenylphosphine)benzylidenerhodium chloride is heated inrefluxing benzene for 8 hours. The mixture is returned to ambienttemperature and diluted with 40 mL of EtOAc. The solution is washedsuccessively with 10 mL each of saturated aqueous NaHCO₃, water, andbrine. The organic phase is dried over MgSO₄, filtered, andconcentrated. Flash chromatography of the crude product yields thedesired product.

Step 2: The product of Step 1 is dissolved in 1 mL of methanol, sealed,and refluxed at 80° C. for 16 h. Volatiles are removed under reducedpressure. Flash chromatography yields the desired product.

What is claimed is:
 1. A compound of the formula

or a pharmaceutically acceptable salt thereof or a stereoisomeric formthereof or a mixture of stereoisomeric forms thereof wherein R_(a) issubstituted or unsubstituted aryl (4-14C); substituted or unsubstitutedarylalkyl (5-20C); substituted or unsubstituted arylalkenyl (5-20C);substituted or unsubstituted arylalkynyl (5-20C); R_(b) is H or halogen;R_(d) is fluoroethyl; and R_(f) is H or C1-C3 alkyl.
 2. The compound ofclaim 1 wherein R_(b) is H.
 3. The compound of claim 1 wherein R_(b) ishalogen.
 4. The compound of claim 1 wherein R_(b) is fluoro.
 5. Thecompound of claim 1 wherein R_(f) is H.
 6. The compound of claim 1wherein R_(f) is C1-C3 alkyl.
 7. The compound of claim 1 wherein R_(f)is methyl.
 8. The compound of claim 1 wherein R_(a) is substituted orunsubstituted aryl (4-14C).
 9. The compound of claim 1 wherein R_(a) issubstituted or unsubstituted arylalkyl (5-20C).
 10. The compound ofclaim 1 wherein R_(a) is substituted or unsubstituted arylalkenyl(5-20C).
 11. The compound of claim 1 wherein R_(a) is substituted orunsubstituted arylalkynyl (5-20C).
 12. The compound of claim 1 whereinR_(a) is 3-aryl-prop-2-enyl or 3-aryl-prop-2-ynyl.
 13. The compound ofclaim 12 wherein said aryl is 3-quinolyl, 4-quinolyl, 5-quinolyl,phenyl, 4-fluorophenyl, 4-chlorophenyl, 4-methoxyphenyl, 6-quinolyl,6-quinoxalyl, 6-amino-3-quinolyl, or 4-isoquinolyl.
 14. The compound ofclaim 1 wherein R_(a) is 3-aryl-prop-2-ynyl.
 15. The compound of claim14 wherein said aryl is 3-quinolyl, 4-quinolyl, 5-quinolyl, phenyl,4-fluorophenyl, 4-chlorophenyl, 4-methoxyphenyl, 6-quinolyl,6-quinoxalyl, 6-amino-3-quinolyl, or 4-isoquinolyl.
 16. A pharmaceuticalcomposition comprising an effective amount of the compound of claim 1 inadmixture with a pharmaceutical acceptable excipient.
 17. A method tocontrol infection in a subject which method comprises administering to asubject in need of such control an effective amount of the compound ofclaim 1 or a pharmaceutical composition thereof.
 18. A method topreserve material from microbial decay which method comprises providingsaid material with an effective amount of the compound of claim
 1. 19. Acompound of the formula

wherein R_(a) is substituted or unsubstituted arylalkyl (5-20C);substituted or unsubstituted arylalkenyl (5-20C); or substituted orunsubstituted arylalkynyl (5-20C). R_(b) is H or F; and, R_(d) isfluoroethyl.
 20. The compound of claim 19 wherein R_(a) is substitutedor unsubstituted arylalkynyl.
 21. The compound of claim 19 wherein R_(a)is substituted or unsubstituted arylalkenyl.
 22. The compound of claim19 wherein R_(a) is 3-aryl-prop-2-ynyl.
 23. The compound of claim 19wherein R_(a) is 3-aryl-prop-2-enyl.
 24. The compound of claim 23wherein the aryl is 3-quinolyl, 4-quinolyl, 5-quinolyl, phenyl,4-fluorophenyl, 4-chlorophenyl, 4-methoxyphenyl, 6-quinolyl,6-quinoxalyl, 6-amino-3-quinolyl, or 4-isoquinolyl.
 25. The compound ofclaim 23 wherein R_(a) is 3-(6-quinoxalyl)-prop-2-enyl; and R_(b) is H.26. The compound of claim 23 wherein R_(a) is3-(3-quinolyl)-prop-2-enyl; and R_(b) is H.
 27. The compound of claim 23wherein R_(a) is 3-(6-quinoxalyl)-prop-2-enyl; and R_(b) is F.
 28. Thecompound of claim 23 wherein R_(a) is 3-(3-quinolyl)-prop-2-enyl; andR_(b) is F.
 29. A compound of the formula

wherein R_(a) is C1-C3 alkyl; R_(d) is fluoroethyl; and R_(f) issubstituted or unsubstituted aryl (4-14C); substituted or unsubstitutedarylalkyl (5-20C).
 30. The compound of claim 29 wherein R_(a) is methyl.31. The compound of claim 30 wherein R_(f) is substituted orunsubstituted arylalkyl (5-20C).
 32. A compound of the formula

wherein R_(a) is C1-C3 alkyl; R_(b) is halogen; R_(d) is fluoroethyl;and R_(f) is substituted or unsubstituted aryl (4-14C); or substitutedor unsubstituted arylalkyl (5-20C).
 33. The compound of claim 32 whereinR_(b) is fluoro.
 34. The compound of claim 33 wherein R_(a) is methyl.35. The compound of claim 34 wherein R_(f) is substituted orunsubstituted arylalkyl (5-20C).